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Home / DTC / P1178 — Mixture 2 strength (multiplicative) fault

P1178 — Mixture 2 strength (multiplicative) fault

Detailed page for trouble code P1178.

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Code

P1178

ALFA ROMEO P — Powertrain

Mixture 2 strength (multiplicative) fault

Brand: ALFA ROMEO
Type: P — Powertrain
Views: UK: 2 EN: 5 RU: 4
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
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Code

P1178

BMW P — Powertrain

O2 Sensor Signal Circuit Slow Switching From Rich to Lean Bank 1 Sensor 1

Brand: BMW
Type: P — Powertrain
Views: UK: 18 EN: 35 RU: 15
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
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Code

P1178

DAEWOO P — Powertrain

ETS MOTOR - SHORT TO BATT

Brand: DAEWOO
Type: P — Powertrain
Views: UK: 2 EN: 8 RU: 7
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
Your experience will help others
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Code

P1178

FIAT P — Powertrain

Mixture 2 strength (multiplicative) fault

Brand: FIAT
Type: P — Powertrain
Views: UK: 3 EN: 7 RU: 4
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
Your experience will help others
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Code

P1178

JAGUAR P — Powertrain

Long Term Fuel Trim Too Lean Banks 1 And 2 (AMFR)

Brand: JAGUAR
Type: P — Powertrain
Views: UK: 19 EN: 41 RU: 18
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
Your experience will help others
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Code

P1178

LAND ROVER P — Powertrain

Banks 1 and 2 long-term fuel very thin gaskets (mass flow rate of air)

Brand: LAND ROVER
Type: P — Powertrain
Views: UK: 2 EN: 11 RU: 6
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
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Workshop Manual
Defender 300Tdi Years: 1996 Manual in English 7.5 MB
Short description

Official workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.

Contents
Key sections:
  • 01 INTRODUCTION
  • 04 GENERAL SPECIFICATION DATA
  • 05 ENGINE TUNING DATA
  • 07 GENERAL FITTING REMINDERS
  • 09 LUBRICANTS, FLUIDS AND CAPACITIES
  • 10 MAINTENANCE
  • 12 ENGINE Tdi
  • - Description and operation
  • - Fault diagnosis
  • - Adjustment
  • - Repair and overhaul procedures
  • 19 FUEL SYSTEM Tdi
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Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)

Workshop Manual
Defender Years: 1999–2002 Manual in English 7.6 MB
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Contents
Key sections:
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  • - Introduction
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  • - References
  • - Repairs and replacements
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Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)

Workshop Manual
Manual in English Pages: 494 7.1 MB
Short description

Land Rover Range Rover Electrical Library (LRL 0453ENG). Comprehensive manual covering fuse details, earth points, system descriptions, diagnostics and connector pin-outs for electrical troubleshooting and repair. Intended for technicians and service workshops.

Contents
Key sections:
  • 1 INTRODUCTION
  • 1.1 About this document
  • 1.2 Battery voltage
  • 1.3 Electrical precautions
  • 1.4 Battery disconnecting / charging
  • 1.5 Disciplines / greases
  • 1.6 Abbreviations
  • 1.7 HeVAC, sensors abbreviations
  • 1.8 How to use this document
  • 1.9 Connector detail format
  • 1.10 Fault diagnosis
  • 1.11 Wire colour codes
Download
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Code

P1178

Other P — Powertrain

( open )

Brand: Other
Type: P — Powertrain
Views: UK: 19 EN: 38 RU: 15
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
Workshop Manuals

Available brands with manuals

2
AUDI 11

6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)

Workshop Manual
Years: 2008 Manual in English Pages: 187 4.9 MB
Short description

Workshop manual for the 6‑speed manual gearbox 0B1 (front‑wheel drive). Includes identification, technical data, gearbox/selector removal & installation procedures, clutch hydraulics, adjustment instructions and front differential service. Applicable to Audi A4, Audi A5 (Coupé, Cabriolet, Sportback) and Audi Q5 as referenced in the manual. Edition: 05.2014.

Contents
Key sections:
  • 00 - Technical data
  • 1 Identification
  • 1.1 Gearbox identification
  • 2 Technical data
  • 2.1 Allocation of gearbox to engine
  • 2.1.1 Allocation - Audi A4 2008 ►
  • 2.1.2 Allocation - Audi A5 Coupé 2008 ►, Audi A5 Sportback 2010 ►
  • 2.1.3 Allocation - Audi A5 Cabriolet 2009 ►
  • 2.1.4 Allocation - Audi Q5 2008 ►
  • 2.2 Capacities
  • 3 Transmission layout
  • 3.1 Transmission layout - front‑wheel drive
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Audi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002

Workshop Manual
Years: 1997 Manual in English Pages: 283 4.3 MB
Short description

Service manual for Audi A3 (1997) 1.6L 4‑cylinder (2‑valve) engines (codes AEH, AKL, APF). Includes technical data, engine removal/installation, crankshaft group, cylinder head and valve gear, lubrication, cooling and exhaust system procedures. Edition 07.2002.

Contents
Key sections:
  • 00 - Technical data ............................................................1
  • 1 Technical data ............................................................1
  • 1.1 Technical data .......................................................1
  • 1.2 Engine number .......................................................1
  • 1.3 Engine data ........................................................1
  • 10 - Removing and installing engine ..........................................3
  • 1 Removing and installing engine .........................................3
  • 1.1 Removing and installing engine ....................................3
  • 1.2 Removing - vehicles with engine codes AEH, AKL .....................4
  • 1.3 Removing - vehicles with engine code APF ..........................18
  • 1.4 Detaching engine from gearbox ...................................35
  • 1.5 Attaching engine to repair stand ................................38
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AUDI A3 (2004) Workshop Manual — 2.0L FSI Turbo (4‑cyl, 4‑valve) Engine, Mechanics — Edition 03.2017

Workshop Manual
Years: 2004 Manual in English Pages: 235 3.8 MB
Short description

Official workshop manual for the Audi A3 2.0L FSI turbo engine (mechanics). Includes step‑by‑step removal/install procedures, technical data, tightening torques and diagnostic/repair instructions. Intended for professional garages and experienced technicians.

Contents
Key sections:
  • 00 - Technical data
  • 1 Engine number
  • 2 Engine data (code letters AXX, BPY, BWA, BHZ, BZC, CDL — capacity, power, torque, bore/stroke, compression, ignition)
  • 3 Safety precautions
  • 3.1 Working on the fuel system
  • 3.2 Procedure before opening high-pressure section
  • 3.3 Working on the cooling system
  • 3.4 Using testers during road test
  • 3.5 Working on the exhaust system
  • 4 General repair instructions
  • 4.1 Cleanliness rules for fuel/injection/turbo
  • 4.2 Checking fuel system for leaks
Download

Audi A3 2004 — Electrical System (Workshop Manual, Edition 02.2018)

Workshop Manual
Years: 2004 Manual in English Pages: 150 68.2 MB
Short description

Workshop manual for the Audi A3 (2004) — Electrical system. Includes procedures for battery, starter, alternator, gauges, wipers, exterior/interior lighting and wiring. Edition 02.2018.

Contents
Key sections:
  • List of Workshop Manual Repair Groups
  • - 27 Starter, current supply, CCS
  • - 90 Gauges, instruments
  • - 92 Windscreen wash/wipe system
  • - 94 Lights, bulbs, switches - exterior
  • - 96 Lights, bulbs, switches - interior
  • - 97 Wiring
  • 27 - Starter, current supply, CCS
  • 1 Contact corrosion
  • 2 Battery
  • 2.1 Battery - general notes
  • 2.2 Maintenance-free batteries
Download

Audi A4 / A4 Cabriolet – 4.2 l V8 (5‑valve, timing chains) – Workshop Manual (Mechanics) – Edition 04.2007

Workshop Manual
Years: 2001–2003 Manual in English Pages: 307 7.3 MB
Short description

Comprehensive workshop manual for Audi A4 (2001) and A4 Cabriolet (2003) with the 4.2 L V8, 5‑valve engine with timing chains (Engine IDs BBK/BHF). Includes step‑by‑step procedures for engine removal/installation, crankshaft and timing chain service, cylinder head/valve gear, lubrication, cooling and exhaust system repairs. Intended for professional technicians and service workshops.

Contents
Key sections:
  • 00 - Technical data
  • 1 Engine number
  • 2 Engine data (Codes: BBK / BHF; 4.163 l; 253 kW @7000 rpm; torque 410–420 Nm; bore 84.5 mm; stroke 92.8 mm; compression ratio 11.5; RON 98)
  • 3 Safety precautions
  • 4 General repair instructions (cleanliness, fuel system, contact corrosion)
  • 10 - Removing and installing engine
  • 1 Removing engine - vehicles with manual gearbox
  • 1.1 Removing engine (tools, drain fluids, remove bumper, lock carrier, disconnect wiring, fuel, coolant, A/C lines, suspension components, propshaft, exhaust, support engine on platform, lower assembly)
  • 1.2 Separating engine and gearbox (subframe removal, support sets, remove front exhaust pipes, bolt sequence)
  • 1.3 Securing engine to engine and gearbox stand (lifting tackle, VAS 6095 support)
  • 1.4 Installing engine (clutch remarks, alignment, torque values)
  • 2 Removing and installing engine - vehicles with automatic gearbox (procedure parallels manual gearbox with ATF/torque converter notes)
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Audi A4 / A4 Cabriolet — Auxiliary Heater Workshop Manual (Edition 08.2004)

Workshop Manual
Years: 2001 Manual in English Pages: 259 2.0 MB
Short description

Workshop Manual for Audi A4 and A4 Cabriolet — Auxiliary Heater (Edition 08.2004). Contains self-diagnosis procedures, fault tables, electrical and fuel system checks, final control tests, CO₂ exhaust adjustment and step-by-step removal/installation and repair procedures. Intended for professional workshop use.

Contents
Key sections:
  • 01 - Self-diagnosis, electrical checks
  • 1 Auxiliary heater self-diagnosis
  • 1.1 Technical data of self-diagnosis
  • 1.2 Function
  • 1.3 Fault recognition
  • 1.4 Guided fault-finding
  • 1.5 Technical data of self-diagnosis
  • 1.6 Test requirements for self-diagnosis
  • 1.7 Safety precautions
  • 2 Self-diagnosis procedure
  • 2.1 Connecting vehicle diagnostic VAS 5051A/K-wire adapter
  • 2.1.1 Control unit identification
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Audi A4 / A4 Cabriolet (1.8T 4‑cyl turbo) — Motronic Injection & Ignition System Service Manual (Edition 01.2015)

Workshop Manual
Years: 2001 Manual in English Pages: 34 851.0 KB
Short description

Service manual for Audi A4 (2001‑) and A4 Cabriolet (2003‑) with 1.8L 4‑cylinder turbo engines. Covers Motronic fuel injection and ignition systems, diagnostic and maintenance procedures. Includes technical data, removal/installation steps and system checks.

Contents
Key sections:
  • 24 - Mixture preparation - injection
  • 1 Safety precautions and rules for cleanliness
  • 1.1 General notes on self-diagnosis
  • 1.2 Safety precautions when using testers and measuring instruments during a road test
  • 1.3 Rules for cleanliness and instructions for working on fuel system
  • 1.4 Checking vacuum system
  • 2 Injection system
  • 2.1 Technical data
  • 2.2 Overview of fitting locations - injection system
  • 3 Intake manifold
  • 3.1 Exploded view - intake manifold
  • 3.2 Removing and installing intake manifold
Download

Audi A8 (2003) — Electrical System Workshop Manual (Edition 08.2014)

Workshop Manual
Years: 2003 Manual in English Pages: 369 9.1 MB
Short description

Comprehensive workshop manual for the Audi A8 (2003) electrical system — Edition 08.2014. Covers battery, alternator, starter, instrument cluster, wiper/washer systems, exterior/interior lighting and wiring repair procedures with step-by-step illustrations. Includes diagnostic and adjustment procedures and torque/data specifications.

Contents
Key sections:
  • 27 - Starter, current supply, CCS
  • 1 Contact corrosion
  • 2 Battery
  • 2.1 Battery - general notes
  • 2.2 Maintenance-free batteries
  • 2.3 Disconnecting and connecting battery
  • 2.4 Removing and installing battery
  • - Remove luggage compartment side trim (right-side)
  • - Connect battery charger for back-up power
  • - Detach earth and positive cables, central venting hose
  • - Remove battery retainer plate and lift battery out
  • - Installation notes, adaptation via Vehicle diagnostic tester
Download

Audi Q4 e-tron (Type F4) - Self-study Programme SSP 685

Workshop Manual
Years: 2021 Manual in English Pages: 186 82.7 MB
Short description

Official Audi Service Training self‑study programme SSP 685 for the Audi Q4 e‑tron (Type F4). Covers body, power units, power transmission, running gear, electrics & electronics, high‑voltage system, thermal management, driver assist and infotainment. Intended for internal service training and technical familiarisation; not a workshop repair manual.

Contents
Key sections:
  • Introduction
  • - Introduction to Audi Q4 e-tron
  • - Dimensions
  • Body
  • - Body structure and materials
  • - Joining techniques
  • - Securing high-voltage battery and force progression
  • - Body assembly (doors, rear lid, panoramic sunroof)
  • - Dash panel and centre console
  • Power units
  • - Technical data: rear electric motor (VX90)
  • - Technical data: front electric motor (VX89)
Download

Audi Q8 (2018) — Electrical System Workshop Manual (Edition 05.2019)

Workshop Manual
Years: 2018 Manual in English Pages: 645 14.8 MB
Short description

Workshop manual for the Audi Q8 (2018) — Electrical System. Includes technical data, safety notes and step‑by‑step repair procedures for battery/charging, starter/alternator, lighting, washer/wiper and wiring. Edition 05.2019.

Contents
Key sections:
  • 00 - Technical data
  • 1 Safety precautions
  • 1.1 Safety precautions when working on vehicles with start/stop system
  • 1.2 Safety precautions when using testers and measuring instruments during a road test
  • 1.3 Notes on use and safety for LED headlights and Audi laser lights
  • 2 Repair notes
  • 2.1 Rules for cleanliness
  • 2.2 General notes
  • 2.3 Contact corrosion
  • 2.4 ESD (electrostatic discharge) workplace
  • 2.5 Routing and attachment of lines and wiring
  • 2.6 Identification plates
Download

Audi Servicing Manual — 7‑Speed Dual Clutch Transmission 0CJ / 0CL / 0CK / 0DN / 0DP / 0HL (Edition 05.2018)

Workshop Manual
Years: 2008–2019 Manual in English Pages: 128 11.1 MB
Short description

Service manual for the 7‑Speed dual‑clutch (DSG) transmissions 0CJ/0CL/0CK/0DN/0DP/0HL fitted to various Audi models. Includes repair information, clutch and gearbox disassembly/assembly, mechatronic and hydraulic system procedures, seals and differential work. Edition 05.2018.

Contents
Key sections:
  • 00 - General, Technical Data
  • 1 Repair Information
  • 1.1 General Repair Information
  • 1.2 Contact Corrosion
  • 1.3 ATF Pump, Deactivating and Draining the Hydraulic Pump Reservoir
  • 2 Rules for Cleanliness when Working on DSG® Transmission
  • 30 - Clutch
  • 1 Clutch
  • 1.1 Overview - Flywheel and Dual Clutch
  • 1.2 Flywheel, Removing and Installing
  • 1.3 Dual Clutch, Removing and Installing
  • 1.4 Input Shaft Seal, Replacing
Download
LAND ROVER 3

Land Rover Defender 300Tdi — Workshop Manual (1996 model year)

Workshop Manual
Defender 300Tdi Years: 1996 Manual in English 7.5 MB
Short description

Official workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.

Contents
Key sections:
  • 01 INTRODUCTION
  • 04 GENERAL SPECIFICATION DATA
  • 05 ENGINE TUNING DATA
  • 07 GENERAL FITTING REMINDERS
  • 09 LUBRICANTS, FLUIDS AND CAPACITIES
  • 10 MAINTENANCE
  • 12 ENGINE Tdi
  • - Description and operation
  • - Fault diagnosis
  • - Adjustment
  • - Repair and overhaul procedures
  • 19 FUEL SYSTEM Tdi
Download

Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)

Workshop Manual
Defender Years: 1999–2002 Manual in English 7.6 MB
Short description

Workshop Manual Supplement and Body Repair Manual for the Land Rover Defender. Includes general specifications, maintenance schedules, tuning data and step‑by‑step repair procedures for engine, transmission, suspension, brakes, electrical and body repairs. Covers Defender models from 1999 and 2002 model years.

Contents
Key sections:
  • 01 - INTRODUCTION
  • - Introduction
  • - Dimensions
  • - References
  • - Repairs and replacements
  • - Poisonous substances
  • - Fuel handling precautions
  • - Synthetic rubber
  • - Recommended sealants
  • - Used engine oil precautions
  • - Accessories and conversions
  • - Wheels and tyres
Download

Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)

Workshop Manual
Manual in English Pages: 494 7.1 MB
Short description

Land Rover Range Rover Electrical Library (LRL 0453ENG). Comprehensive manual covering fuse details, earth points, system descriptions, diagnostics and connector pin-outs for electrical troubleshooting and repair. Intended for technicians and service workshops.

Contents
Key sections:
  • 1 INTRODUCTION
  • 1.1 About this document
  • 1.2 Battery voltage
  • 1.3 Electrical precautions
  • 1.4 Battery disconnecting / charging
  • 1.5 Disciplines / greases
  • 1.6 Abbreviations
  • 1.7 HeVAC, sensors abbreviations
  • 1.8 How to use this document
  • 1.9 Connector detail format
  • 1.10 Fault diagnosis
  • 1.11 Wire colour codes
Download
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Code

P1178

VOLKSWAGEN P — Powertrain

Linear Oxygen Sensor Pump Current Open

Brand: VOLKSWAGEN
Type: P — Powertrain
Views: UK: 23 EN: 58 RU: 29
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Intake vacuum leak or air leak downstream of the MAF (bank 2)
  • Faulty or contaminated MAF or MAP sensor
  • Faulty or drifting oxygen sensor (narrowband or wideband) on bank 2
  • Fuel delivery problem (low fuel pressure, weak pump, clogged filter)
  • Leaking or clogged fuel injector(s) on bank 2
  • Exhaust leak upstream of O2 sensor on bank 2

Symptoms

  • Illuminated check engine light (MIL)
  • Poor idle or rough running on the affected bank
  • Reduced fuel economy
  • Hesitation, stumbling or loss of power under load
  • Black exhaust smoke (rich) or misfire/lean symptoms
  • Difficulty starting or extended crank time

What to check

  • Read freeze-frame data and scan live data for fuel trims, O2 voltages, MAF/MAP readings and fuel pressure
  • Check for additional DTCs (O2 sensor, fuel trim, MAF, misfire codes)
  • Visually inspect intake hoses, vacuum lines and PCV system for leaks or damage
  • Perform smoke test of intake and vacuum system if leaks are suspected
  • Check MAF sensor condition and wiring; clean or replace if contaminated
  • Measure fuel rail pressure at idle and under load, compare to spec

Signal parameters

  • Long-term fuel trim (LTFT) bank 2: normally within approx. -10% to +10% (varies by model)
  • Short-term fuel trim (STFT) bank 2: small rapid corrections around 0% during closed-loop
  • Narrowband O2 voltage (if equipped): ~0.1–0.9 V switching in closed-loop
  • Wideband O2/lambda: lambda ≈ 1.00 in stoichiometric conditions; check manufacturer ranges
  • MAF sensor: stable, proportional airflow reading for RPM/load; check grams/sec or V per spec
  • Fuel rail pressure: within manufacturer specified range at idle and under load

Diagnostic algorithm

  1. Record all stored codes and freeze-frame data. Clear codes and attempt to reproduce while monitoring live PID values (LTFT, STFT, O2 sensors, MAF, MAP, fuel pressure).
  2. Inspect intake boots, vacuum lines, intercooler/boost hoses (if turbo) and PCV connections on bank 2 for cracks, loose clamps or leaks. Perform a smoke test if available.
  3. Check for exhaust leaks before the bank 2 O2 sensor which can cause false lean readings.
  4. Inspect and test the MAF sensor: check wiring and connector, clean MAF with appropriate cleaner, and confirm readings change sensibly with throttle.
  5. Verify fuel delivery: measure static and under-load fuel pressure and compare to spec; inspect fuel filter and pump operation.
  6. Monitor O2 sensor(s) for bank 2: check heater operation, sensor voltage/AFR response speed and compare to bank 1 behavior. Replace slow or out-of-range sensors.
  7. Perform injector balance test on bank 2 (electrical and flow) and inspect for leaking or clogged injectors.
  8. Check wiring and grounds to ECU, O2 sensors and injectors for continuity, shorts to power/ground, and corrosion. Repair any faults.
  9. If all sensors and hardware check OK, review ECU software/calibration updates and consider ECU bench diagnostics or replacement as a last resort.
  10. After repairs, clear adaptive fuel trims and road-test to verify LTFT returns to normal and the P1178 does not reappear.

Likely causes

  • Intake or vacuum leak on bank 2 (most common)
  • Failed or out-of-spec O2 (lambda) sensor on bank 2
  • MAF sensor contamination or failure
  • Low fuel pressure or faulty fuel regulator
  • Wiring/connector problem to O2 sensor or injectors

Fault status

⚠️ Status
Mixture strength (multiplicative) for bank 2 out of expected range — fuel trim compensation abnormal. Inspect for air/fuel imbalance, sensor or wiring faults.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.5 to 4 hours (varies by access, required tests and parts)
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
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