Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's computer is having trouble resetting the part that makes the engine go faster or slower on one side of the engine.
The engine control module (ECM) is unable to reset the throttle actuator correctly for bank 2, which can affect engine performance.
The throttle actuator is responsible for controlling the amount of air entering the engine. Bank 2 refers to the side of the engine that does not contain cylinder 1. This code indicates a problem with the monitoring and reset function of the throttle actuator on this side, which could be due to electrical, mechanical, or software issues.
• Check Engine Light is on
• Reduced engine performance
• Hesitation or stalling
• Faulty throttle actuator
• Wiring issues or poor connections
• ECM software glitch
Throttle Actuator: A device that controls the airflow to the engine.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle actuator and related wiring for damage.
• Check for software updates for the ECM.
• Replace the throttle actuator if faulty.
• Repair or replace damaged wiring or connectors.
• Update or reprogram the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• BMW 3 Series
• Mercedes-Benz C-Class
• Audi A4
• Regular maintenance checks
• Ensure software updates are applied
• Inspect wiring and connectors periodically
Throttle Control Issue
• Drive cautiously and avoid heavy acceleration.
• Schedule a service appointment with a qualified mechanic.
Check with your vehicle manufacturer for warranty coverage on throttle control components.
Throttle actuator issues have been more common in vehicles with electronic throttle control systems introduced in the late 2000s.
Moderate – While the vehicle may still be drivable, performance issues should be addressed to prevent further damage.
Ignoring this code could lead to reduced performance and potential safety risks. Always address Check Engine Light issues promptly.
• Engine at operating temperature
• Vehicle stationary and in park or neutral
The throttle actuator is typically located on the intake manifold, near the throttle body, on the side of the engine opposite cylinder 1.
Q: Can I drive with a P155F code?
A: It's possible to drive, but not recommended due to potential performance issues.
Q: Will a P155F code cause my car to fail emissions tests?
A: Yes, it can cause your car to fail emissions tests due to improper air-fuel mixture control.
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