BMW DTC P108F – Idle Air Control System in H2 Operation RPM Higher Than Expected
DTC P108F meaning on BMW
DTC P108F on a BMW indicates an issue with the Idle Air Control (IAC) system during H2 operation, where the engine’s RPM is higher than expected. The IAC system is responsible for controlling the engine’s idle speed by regulating the amount of air entering the engine.
BMW DTC P108F symptoms
Symptoms of DTC P108F on a BMW may include:
- Higher than normal idle RPM
- Engine surging or fluctuating idle speed
- Possible stalling at idle
- Check Engine Light (CEL) illuminated on the dashboard
BMW DTC P108F causes
Common causes of DTC P108F on a BMW include:
- Faulty Idle Air Control (IAC) valve
- Vacuum leaks in the intake system
- Dirty or clogged throttle body
- Issues with the engine’s air intake system
BMW DTC P108F seriousness
While DTC P108F may not cause immediate drivability issues, it can lead to poor engine performance, reduced fuel efficiency, and potential stalling. Ignoring this fault can result in further damage to engine components over time.
How to diagnose DTC P108F on BMW
To diagnose DTC P108F on a BMW, a mechanic may perform the following steps:
- Use a diagnostic scanner to retrieve the fault code and freeze frame data
- Inspect the Idle Air Control (IAC) valve for proper operation
- Check for vacuum leaks in the intake system
- Clean the throttle body and inspect for any obstructions
- Perform a visual inspection of the air intake system components
How to fix DTC P108F on BMW
To fix DTC P108F on a BMW, the following steps may be taken:
- Replace the faulty Idle Air Control (IAC) valve
- Repair any vacuum leaks in the intake system
- Clean the throttle body to ensure smooth airflow
- Address any issues with the engine’s air intake system
- Clear the fault code and reset the Check Engine Light
How to erase DTC P108F on BMW
To erase DTC P108F on a BMW, the fault code can be cleared using a diagnostic scanner. After addressing the underlying issue causing the fault code, the scanner can be used to reset the Check Engine Light and clear the DTC from the vehicle’s memory.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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