Code
P02A1
Generic
P — Powertrain
Cylinder 2 - Injector Leaking
Views:
UK: 12
EN: 16
RU: 12
AI status
Completed
Completed
100%
Causes
- Failed or stuck open fuel injector (internal leak)
- Worn or damaged injector seals/O-rings allowing external leak into intake or crankcase
- Leak in injector return/bleed line (diesel systems) or rail/drain passage
- Low injector control resistance or short to battery causing partial opening
- Faulty PCM or incorrect calibration (less common)
- Fuel rail pressure regulator or check valve fault allowing backflow
Symptoms
- Rough idle and/or misfire on cylinder 2
- Poor fuel economy and increased emissions
- Strong fuel smell or visible fuel leak near injector
- Fuel dilution of engine oil (diesel especially)
- Hard starting or extended cranking
- Lower than normal fuel rail pressure or slow pressure recovery
What to check
- Read freeze frame and stored data: fuel rail pressure, engine load, RPM, coolant temp when DTC set
- Visual inspection for external fuel leaks at injector, rail, hoses and connectors
- Inspect injector O-rings and seating for damage
- Check injector harness and connector for corrosion, continuity, short to power or ground
- Measure injector coil resistance and compare to spec
- Perform cylinder contribution/balance or power balance test
Signal parameters
- Injector coil resistance: typical solenoid 1–3 Ω (low-impedance) or 10–18 Ω (high-impedance) — check OEM spec
- Injector activation pulse width: varies with load; steady battery-level supply when not driven
- Fuel rail pressure: should remain within spec and not drop quickly when engine off or during cranking
- Leakage threshold (diagnostic): any measurable leak when injector closed that allows fuel into cylinder or return path; manufacturer thresholds vary
- Injector drive voltage: ~12 V supply, switched to ground by PCM; no constant supply when engine running except during commanded pulses
Diagnostic algorithm
- Retrieve DTCs and freeze-frame data. Confirm P02A1 and note conditions when set.
- Safety: relieve fuel system pressure and remove ignition sources before servicing injectors.
- Visually inspect injector #2, O-rings, rail and nearby hoses for fuel. Repair visible external leaks.
- With connector disconnected, check for fuel presence in the intake port (engine off, crank slowly). Excess fuel indicates leaking injector.
- Measure injector coil resistance and compare to OEM spec. Abnormal values suggest internal failure.
- Perform an injector on/off functional test (bidirectional scan tool) while monitoring fuel pressure; a leaking injector will cause persistent pressure drop or fuel flow during closed periods.
- Perform a fuel rail pressure leak-down test: pressurize rail, isolate pump, monitor pressure. Rapid pressure loss indicates internal or external leak.
- For diesel common-rail systems, perform return/bleed flow measurement on injector #2. Excess flow equals leaking injector.
- Swap injector #2 with another cylinder (if identical) and re-run tests/clear codes to see if fault follows injector. Do not forget to mark and reinstall correctly.
- If electrical anomaly suspected, check harness for short to power/ground and inspect PCM driver output. Repair wiring or replace PCM if proven faulty.
- After repair or replacement, clear codes and road/test to confirm DTC does not return and symptoms are resolved.
Likely causes
- Internal injector leakage (most common)
- Damaged O-ring or sealing surface at injector
- Clogged or damaged injector return/drain line (diesel)
- Electrical fault causing continuous drive
Fault status
Status
DTC P02A1 — Cylinder 2 injector leaking. PCM detected abnormal fuel flow or pressure behavior attributable to injector #2 allowing fuel when it should be closed.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
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Code
P02A1
LAND ROVER
P — Powertrain
Cylinder 2 Balance - Injector Leak
Views:
UK: 6
EN: 9
RU: 5
AI status
Completed
Completed
100%
Causes
- Failed or stuck open fuel injector (internal leak)
- Worn or damaged injector seals/O-rings allowing external leak into intake or crankcase
- Leak in injector return/bleed line (diesel systems) or rail/drain passage
- Low injector control resistance or short to battery causing partial opening
- Faulty PCM or incorrect calibration (less common)
- Fuel rail pressure regulator or check valve fault allowing backflow
Symptoms
- Rough idle and/or misfire on cylinder 2
- Poor fuel economy and increased emissions
- Strong fuel smell or visible fuel leak near injector
- Fuel dilution of engine oil (diesel especially)
- Hard starting or extended cranking
- Lower than normal fuel rail pressure or slow pressure recovery
What to check
- Read freeze frame and stored data: fuel rail pressure, engine load, RPM, coolant temp when DTC set
- Visual inspection for external fuel leaks at injector, rail, hoses and connectors
- Inspect injector O-rings and seating for damage
- Check injector harness and connector for corrosion, continuity, short to power or ground
- Measure injector coil resistance and compare to spec
- Perform cylinder contribution/balance or power balance test
Signal parameters
- Injector coil resistance: typical solenoid 1–3 Ω (low-impedance) or 10–18 Ω (high-impedance) — check OEM spec
- Injector activation pulse width: varies with load; steady battery-level supply when not driven
- Fuel rail pressure: should remain within spec and not drop quickly when engine off or during cranking
- Leakage threshold (diagnostic): any measurable leak when injector closed that allows fuel into cylinder or return path; manufacturer thresholds vary
- Injector drive voltage: ~12 V supply, switched to ground by PCM; no constant supply when engine running except during commanded pulses
Diagnostic algorithm
- Retrieve DTCs and freeze-frame data. Confirm P02A1 and note conditions when set.
- Safety: relieve fuel system pressure and remove ignition sources before servicing injectors.
- Visually inspect injector #2, O-rings, rail and nearby hoses for fuel. Repair visible external leaks.
- With connector disconnected, check for fuel presence in the intake port (engine off, crank slowly). Excess fuel indicates leaking injector.
- Measure injector coil resistance and compare to OEM spec. Abnormal values suggest internal failure.
- Perform an injector on/off functional test (bidirectional scan tool) while monitoring fuel pressure; a leaking injector will cause persistent pressure drop or fuel flow during closed periods.
- Perform a fuel rail pressure leak-down test: pressurize rail, isolate pump, monitor pressure. Rapid pressure loss indicates internal or external leak.
- For diesel common-rail systems, perform return/bleed flow measurement on injector #2. Excess flow equals leaking injector.
- Swap injector #2 with another cylinder (if identical) and re-run tests/clear codes to see if fault follows injector. Do not forget to mark and reinstall correctly.
- If electrical anomaly suspected, check harness for short to power/ground and inspect PCM driver output. Repair wiring or replace PCM if proven faulty.
- After repair or replacement, clear codes and road/test to confirm DTC does not return and symptoms are resolved.
Likely causes
- Internal injector leakage (most common)
- Damaged O-ring or sealing surface at injector
- Clogged or damaged injector return/drain line (diesel)
- Electrical fault causing continuous drive
Fault status
Status
DTC P02A1 — Cylinder 2 injector leaking. PCM detected abnormal fuel flow or pressure behavior attributable to injector #2 allowing fuel when it should be closed.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Workshop Manuals
Repair manuals for LAND ROVER
3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
+100 karma for a short comment :)
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