Fault code P1152 – a step-by-step guide to diagnosing and fixing it

Error code P1152 is displayed and the check engine light is on - what does this mean?

The OBD/EOBD system has detected a fault in the fuel mixture control circuit, which indicates that the mixture in bank 2 is too lean. This DTC P1152 mainly affects the fuel system, the lambda sensors and the injection system. This trouble code can have slightly different meanings for different manufacturers, but generally refers to problems with the fuel-air mixture.

What causes can this error code have?

• Defective lambda sensor in bank 2
• Blocked or defective fuel injectors
• Damaged vacuum hoses
• Defective fuel pressure regulator
• Dirty mass air flow sensor
• Leaks in the intake tract
• Defective fuel pump
• Clogged fuel filter
• Loose or corroded plug connections
• Defective engine control unit

What symptoms occur in parallel with fault code P1152?

• Loss of engine power: Noticeable reduction in engine power, especially at higher engine speeds
• Unsteady idling: Engine runs unevenly or stutters at idle speed
• Increased fuel consumption: Significantly higher consumption despite normal driving behavior
• Starting problems: Difficulty starting, especially when the engine is cold
• Jerking while driving: Uneven engine running at constant speed
• Exhaust problems: Increased emission values during the emissions test

How can the problem with error code P1152 be rectified?

• The repair requires a systematic diagnosis to identify the exact cause.
• Check lambda sensor bank 2 and replace if necessary: Perform resistance measurement and check signal voltage, replace defective sensor
• Check fuel pressure system: Measure fuel pressure, replace fuel filter and fuel pump if pressure is insufficient
• Clean or replace injection nozzles: Test flow rate and have clogged nozzles professionally cleaned or replaced
• Check vacuum lines: Check all hoses for cracks and leaks, replace damaged parts
• Clean mass air flow sensor: Clean sensor with special cleaner or replace completely if defective
• Check the intake tract for leaks: Carry out a smoke test and seal any leaks or replace components