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Home / DTC / P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1

P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1

Detailed page for trouble code P0191.

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P0191

Generic P — Powertrain

Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1

Brand: Generic
Type: P — Powertrain
Views: UK: 26 EN: 120 RU: 85
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty fuel rail pressure sensor (Bank 1)
  • Open, shorted or corroded wiring/connector between sensor and ECM
  • Poor sensor reference voltage or ground (ECM supply issue)
  • Contaminated or damaged fuel rail/pressure port
  • Fuel pressure regulator or high-pressure pump malfunction
  • Intermittent connection or wiring chafing

Symptoms

  • MIL illuminated
  • Reduced engine power or limp-home mode
  • Hard starting or extended cranking
  • Rough idle, stalling or surging under load
  • Poor fuel economy
  • Possible fuel odor or leaks (if pressure system compromised)

What to check

  • Scan for P0191 and any related codes; record freeze frame and live data of fuel rail pressure and commanded pressure
  • Perform a visual inspection of FRPS connector, wiring harness and fuel rail for damage, corrosion or contamination
  • Backprobe the sensor connector to measure signal voltage, reference voltage and ground with key ON and engine running
  • Wiggle wiring and connectors while monitoring live data for intermittent changes
  • Compare sensor voltage to manufacturer specifications (or expected generic ranges)
  • Measure fuel rail pressure with a mechanical or OEM diagnostic pressure gauge to verify actual pressure

Signal parameters

  • Typical FRPS signal: approximately 0.5–4.5 V proportional to rail pressure (varies by model) — always confirm vehicle factory spec
  • Reference supply: typically ~5.0 V from ECM on the reference pin (check OEM data)
  • Ground: near 0 V with good continuity to battery negative
  • Expected behavior: signal increases smoothly with increasing rail pressure; no sudden jumps, drops to 0 V, or constant fixed voltage
  • If present, CAN or serial diagnostic parameters should show commanded pressure vs. actual pressure disagreement

Diagnostic algorithm

  1. Retrieve codes and freeze-frame/live-data. Note engine conditions when P0191 set (RPM, temperature, commanded pressure).
  2. Visually inspect sensor, connector and wiring for damage, corrosion, pins pushed out, moisture or fuel contamination. Repair obvious issues.
  3. With connector connected, backprobe sensor pins: verify reference voltage (≈5 V) with key ON, verify sensor ground continuity to battery negative, and measure signal voltage at key ON and during cranking/idle. Look for plausible changes with throttle. Compare to spec.
  4. Wiggle test wiring and connector while monitoring live signal for intermittent faults. Repair any intermittent wiring found.
  5. If reference or ground is out of range, trace and repair power/ground circuits to ECM; check for blown fuses or poor chassis grounds.
  6. If electrical checks are good but signal is out of expected range or non-linear, remove sensor and bench-test per OE procedure (resistance or output vs applied pressure) or replace sensor and re-test.
  7. Independently measure actual fuel rail pressure with a mechanical pressure gauge or OEM fuel pressure tool. Compare measured pressure to commanded pressure; if pressure control components (pump, regulator, control valve) are faulty, repair accordingly.
  8. If swapping sensor known-good cures the issue, replace sensor. If wiring harness or ECM input circuit fault is confirmed, repair wiring or consult OEM before replacing ECM.
  9. Clear codes and perform a test drive to confirm repair and that P0191 does not return.

Likely causes

  • Damaged connector pins or corrosion at sensor harness
  • Short to ground or short to voltage on the sensor signal wire
  • Failed FRPS (internal sensor fault)
  • Loose or poor ground at engine/ECM chassis ground

Fault status

⚠️ Status
P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1. ECM detected sensor signal outside expected range or inconsistent with commanded fuel pressure; MIL illuminated.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

P0190 P0192 P0193 P0194 P0087 P0088
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Code

P0191

GWM P — Powertrain

- Invalid indicator / fuel temperature sensor not adjusted

Brand: GWM
Type: P — Powertrain
Views: UK: 4 EN: 9 RU: 17
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty fuel rail pressure sensor (Bank 1)
  • Open, shorted or corroded wiring/connector between sensor and ECM
  • Poor sensor reference voltage or ground (ECM supply issue)
  • Contaminated or damaged fuel rail/pressure port
  • Fuel pressure regulator or high-pressure pump malfunction
  • Intermittent connection or wiring chafing

Symptoms

  • MIL illuminated
  • Reduced engine power or limp-home mode
  • Hard starting or extended cranking
  • Rough idle, stalling or surging under load
  • Poor fuel economy
  • Possible fuel odor or leaks (if pressure system compromised)

What to check

  • Scan for P0191 and any related codes; record freeze frame and live data of fuel rail pressure and commanded pressure
  • Perform a visual inspection of FRPS connector, wiring harness and fuel rail for damage, corrosion or contamination
  • Backprobe the sensor connector to measure signal voltage, reference voltage and ground with key ON and engine running
  • Wiggle wiring and connectors while monitoring live data for intermittent changes
  • Compare sensor voltage to manufacturer specifications (or expected generic ranges)
  • Measure fuel rail pressure with a mechanical or OEM diagnostic pressure gauge to verify actual pressure

Signal parameters

  • Typical FRPS signal: approximately 0.5–4.5 V proportional to rail pressure (varies by model) — always confirm vehicle factory spec
  • Reference supply: typically ~5.0 V from ECM on the reference pin (check OEM data)
  • Ground: near 0 V with good continuity to battery negative
  • Expected behavior: signal increases smoothly with increasing rail pressure; no sudden jumps, drops to 0 V, or constant fixed voltage
  • If present, CAN or serial diagnostic parameters should show commanded pressure vs. actual pressure disagreement

Diagnostic algorithm

  1. Retrieve codes and freeze-frame/live-data. Note engine conditions when P0191 set (RPM, temperature, commanded pressure).
  2. Visually inspect sensor, connector and wiring for damage, corrosion, pins pushed out, moisture or fuel contamination. Repair obvious issues.
  3. With connector connected, backprobe sensor pins: verify reference voltage (≈5 V) with key ON, verify sensor ground continuity to battery negative, and measure signal voltage at key ON and during cranking/idle. Look for plausible changes with throttle. Compare to spec.
  4. Wiggle test wiring and connector while monitoring live signal for intermittent faults. Repair any intermittent wiring found.
  5. If reference or ground is out of range, trace and repair power/ground circuits to ECM; check for blown fuses or poor chassis grounds.
  6. If electrical checks are good but signal is out of expected range or non-linear, remove sensor and bench-test per OE procedure (resistance or output vs applied pressure) or replace sensor and re-test.
  7. Independently measure actual fuel rail pressure with a mechanical pressure gauge or OEM fuel pressure tool. Compare measured pressure to commanded pressure; if pressure control components (pump, regulator, control valve) are faulty, repair accordingly.
  8. If swapping sensor known-good cures the issue, replace sensor. If wiring harness or ECM input circuit fault is confirmed, repair wiring or consult OEM before replacing ECM.
  9. Clear codes and perform a test drive to confirm repair and that P0191 does not return.

Likely causes

  • Damaged connector pins or corrosion at sensor harness
  • Short to ground or short to voltage on the sensor signal wire
  • Failed FRPS (internal sensor fault)
  • Loose or poor ground at engine/ECM chassis ground

Fault status

⚠️ Status
P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1. ECM detected sensor signal outside expected range or inconsistent with commanded fuel pressure; MIL illuminated.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

P0190 P0192 P0193 P0194 P0087 P0088
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P0191

HUMMER P — Powertrain

Fuel Rail Pressure Sensor Circuit Performance

Brand: HUMMER
Type: P — Powertrain
Views: UK: 13 EN: 36 RU: 49
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty fuel rail pressure sensor (Bank 1)
  • Open, shorted or corroded wiring/connector between sensor and ECM
  • Poor sensor reference voltage or ground (ECM supply issue)
  • Contaminated or damaged fuel rail/pressure port
  • Fuel pressure regulator or high-pressure pump malfunction
  • Intermittent connection or wiring chafing

Symptoms

  • MIL illuminated
  • Reduced engine power or limp-home mode
  • Hard starting or extended cranking
  • Rough idle, stalling or surging under load
  • Poor fuel economy
  • Possible fuel odor or leaks (if pressure system compromised)

What to check

  • Scan for P0191 and any related codes; record freeze frame and live data of fuel rail pressure and commanded pressure
  • Perform a visual inspection of FRPS connector, wiring harness and fuel rail for damage, corrosion or contamination
  • Backprobe the sensor connector to measure signal voltage, reference voltage and ground with key ON and engine running
  • Wiggle wiring and connectors while monitoring live data for intermittent changes
  • Compare sensor voltage to manufacturer specifications (or expected generic ranges)
  • Measure fuel rail pressure with a mechanical or OEM diagnostic pressure gauge to verify actual pressure

Signal parameters

  • Typical FRPS signal: approximately 0.5–4.5 V proportional to rail pressure (varies by model) — always confirm vehicle factory spec
  • Reference supply: typically ~5.0 V from ECM on the reference pin (check OEM data)
  • Ground: near 0 V with good continuity to battery negative
  • Expected behavior: signal increases smoothly with increasing rail pressure; no sudden jumps, drops to 0 V, or constant fixed voltage
  • If present, CAN or serial diagnostic parameters should show commanded pressure vs. actual pressure disagreement

Diagnostic algorithm

  1. Retrieve codes and freeze-frame/live-data. Note engine conditions when P0191 set (RPM, temperature, commanded pressure).
  2. Visually inspect sensor, connector and wiring for damage, corrosion, pins pushed out, moisture or fuel contamination. Repair obvious issues.
  3. With connector connected, backprobe sensor pins: verify reference voltage (≈5 V) with key ON, verify sensor ground continuity to battery negative, and measure signal voltage at key ON and during cranking/idle. Look for plausible changes with throttle. Compare to spec.
  4. Wiggle test wiring and connector while monitoring live signal for intermittent faults. Repair any intermittent wiring found.
  5. If reference or ground is out of range, trace and repair power/ground circuits to ECM; check for blown fuses or poor chassis grounds.
  6. If electrical checks are good but signal is out of expected range or non-linear, remove sensor and bench-test per OE procedure (resistance or output vs applied pressure) or replace sensor and re-test.
  7. Independently measure actual fuel rail pressure with a mechanical pressure gauge or OEM fuel pressure tool. Compare measured pressure to commanded pressure; if pressure control components (pump, regulator, control valve) are faulty, repair accordingly.
  8. If swapping sensor known-good cures the issue, replace sensor. If wiring harness or ECM input circuit fault is confirmed, repair wiring or consult OEM before replacing ECM.
  9. Clear codes and perform a test drive to confirm repair and that P0191 does not return.

Likely causes

  • Damaged connector pins or corrosion at sensor harness
  • Short to ground or short to voltage on the sensor signal wire
  • Failed FRPS (internal sensor fault)
  • Loose or poor ground at engine/ECM chassis ground

Fault status

⚠️ Status
P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1. ECM detected sensor signal outside expected range or inconsistent with commanded fuel pressure; MIL illuminated.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

P0190 P0192 P0193 P0194 P0087 P0088
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

P0191

LAND ROVER P — Powertrain

Malfunction of the fuel rail pressure sensor range / performance

Brand: LAND ROVER
Type: P — Powertrain
Views: UK: 5 EN: 22 RU: 38
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty fuel rail pressure sensor (Bank 1)
  • Open, shorted or corroded wiring/connector between sensor and ECM
  • Poor sensor reference voltage or ground (ECM supply issue)
  • Contaminated or damaged fuel rail/pressure port
  • Fuel pressure regulator or high-pressure pump malfunction
  • Intermittent connection or wiring chafing

Symptoms

  • MIL illuminated
  • Reduced engine power or limp-home mode
  • Hard starting or extended cranking
  • Rough idle, stalling or surging under load
  • Poor fuel economy
  • Possible fuel odor or leaks (if pressure system compromised)

What to check

  • Scan for P0191 and any related codes; record freeze frame and live data of fuel rail pressure and commanded pressure
  • Perform a visual inspection of FRPS connector, wiring harness and fuel rail for damage, corrosion or contamination
  • Backprobe the sensor connector to measure signal voltage, reference voltage and ground with key ON and engine running
  • Wiggle wiring and connectors while monitoring live data for intermittent changes
  • Compare sensor voltage to manufacturer specifications (or expected generic ranges)
  • Measure fuel rail pressure with a mechanical or OEM diagnostic pressure gauge to verify actual pressure

Signal parameters

  • Typical FRPS signal: approximately 0.5–4.5 V proportional to rail pressure (varies by model) — always confirm vehicle factory spec
  • Reference supply: typically ~5.0 V from ECM on the reference pin (check OEM data)
  • Ground: near 0 V with good continuity to battery negative
  • Expected behavior: signal increases smoothly with increasing rail pressure; no sudden jumps, drops to 0 V, or constant fixed voltage
  • If present, CAN or serial diagnostic parameters should show commanded pressure vs. actual pressure disagreement

Diagnostic algorithm

  1. Retrieve codes and freeze-frame/live-data. Note engine conditions when P0191 set (RPM, temperature, commanded pressure).
  2. Visually inspect sensor, connector and wiring for damage, corrosion, pins pushed out, moisture or fuel contamination. Repair obvious issues.
  3. With connector connected, backprobe sensor pins: verify reference voltage (≈5 V) with key ON, verify sensor ground continuity to battery negative, and measure signal voltage at key ON and during cranking/idle. Look for plausible changes with throttle. Compare to spec.
  4. Wiggle test wiring and connector while monitoring live signal for intermittent faults. Repair any intermittent wiring found.
  5. If reference or ground is out of range, trace and repair power/ground circuits to ECM; check for blown fuses or poor chassis grounds.
  6. If electrical checks are good but signal is out of expected range or non-linear, remove sensor and bench-test per OE procedure (resistance or output vs applied pressure) or replace sensor and re-test.
  7. Independently measure actual fuel rail pressure with a mechanical pressure gauge or OEM fuel pressure tool. Compare measured pressure to commanded pressure; if pressure control components (pump, regulator, control valve) are faulty, repair accordingly.
  8. If swapping sensor known-good cures the issue, replace sensor. If wiring harness or ECM input circuit fault is confirmed, repair wiring or consult OEM before replacing ECM.
  9. Clear codes and perform a test drive to confirm repair and that P0191 does not return.

Likely causes

  • Damaged connector pins or corrosion at sensor harness
  • Short to ground or short to voltage on the sensor signal wire
  • Failed FRPS (internal sensor fault)
  • Loose or poor ground at engine/ECM chassis ground

Fault status

⚠️ Status
P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1. ECM detected sensor signal outside expected range or inconsistent with commanded fuel pressure; MIL illuminated.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

P0190 P0192 P0193 P0194 P0087 P0088
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Code

P0191

MITSUBISHI P — Powertrain

Fuel pressure sensor range

Brand: MITSUBISHI
Type: P — Powertrain
Views: UK: 12 EN: 43 RU: 51
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty fuel rail pressure sensor (Bank 1)
  • Open, shorted or corroded wiring/connector between sensor and ECM
  • Poor sensor reference voltage or ground (ECM supply issue)
  • Contaminated or damaged fuel rail/pressure port
  • Fuel pressure regulator or high-pressure pump malfunction
  • Intermittent connection or wiring chafing

Symptoms

  • MIL illuminated
  • Reduced engine power or limp-home mode
  • Hard starting or extended cranking
  • Rough idle, stalling or surging under load
  • Poor fuel economy
  • Possible fuel odor or leaks (if pressure system compromised)

What to check

  • Scan for P0191 and any related codes; record freeze frame and live data of fuel rail pressure and commanded pressure
  • Perform a visual inspection of FRPS connector, wiring harness and fuel rail for damage, corrosion or contamination
  • Backprobe the sensor connector to measure signal voltage, reference voltage and ground with key ON and engine running
  • Wiggle wiring and connectors while monitoring live data for intermittent changes
  • Compare sensor voltage to manufacturer specifications (or expected generic ranges)
  • Measure fuel rail pressure with a mechanical or OEM diagnostic pressure gauge to verify actual pressure

Signal parameters

  • Typical FRPS signal: approximately 0.5–4.5 V proportional to rail pressure (varies by model) — always confirm vehicle factory spec
  • Reference supply: typically ~5.0 V from ECM on the reference pin (check OEM data)
  • Ground: near 0 V with good continuity to battery negative
  • Expected behavior: signal increases smoothly with increasing rail pressure; no sudden jumps, drops to 0 V, or constant fixed voltage
  • If present, CAN or serial diagnostic parameters should show commanded pressure vs. actual pressure disagreement

Diagnostic algorithm

  1. Retrieve codes and freeze-frame/live-data. Note engine conditions when P0191 set (RPM, temperature, commanded pressure).
  2. Visually inspect sensor, connector and wiring for damage, corrosion, pins pushed out, moisture or fuel contamination. Repair obvious issues.
  3. With connector connected, backprobe sensor pins: verify reference voltage (≈5 V) with key ON, verify sensor ground continuity to battery negative, and measure signal voltage at key ON and during cranking/idle. Look for plausible changes with throttle. Compare to spec.
  4. Wiggle test wiring and connector while monitoring live signal for intermittent faults. Repair any intermittent wiring found.
  5. If reference or ground is out of range, trace and repair power/ground circuits to ECM; check for blown fuses or poor chassis grounds.
  6. If electrical checks are good but signal is out of expected range or non-linear, remove sensor and bench-test per OE procedure (resistance or output vs applied pressure) or replace sensor and re-test.
  7. Independently measure actual fuel rail pressure with a mechanical pressure gauge or OEM fuel pressure tool. Compare measured pressure to commanded pressure; if pressure control components (pump, regulator, control valve) are faulty, repair accordingly.
  8. If swapping sensor known-good cures the issue, replace sensor. If wiring harness or ECM input circuit fault is confirmed, repair wiring or consult OEM before replacing ECM.
  9. Clear codes and perform a test drive to confirm repair and that P0191 does not return.

Likely causes

  • Damaged connector pins or corrosion at sensor harness
  • Short to ground or short to voltage on the sensor signal wire
  • Failed FRPS (internal sensor fault)
  • Loose or poor ground at engine/ECM chassis ground

Fault status

⚠️ Status
P0191 — Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1. ECM detected sensor signal outside expected range or inconsistent with commanded fuel pressure; MIL illuminated.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-3.0 hours

Similar codes

P0190 P0192 P0193 P0194 P0087 P0088
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