Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer thinks the engine is not idling at the right speed when running on hydrogen (H2). It's like when you're trying to keep a toy spinning at a certain speed, but it keeps going slower than you want.
The engine control module (ECM) has detected that the idle speed is lower than expected when the vehicle is operating on hydrogen fuel.
The P108E code indicates a discrepancy between the expected and actual idle RPM when the engine is operating in hydrogen mode. This can be due to various factors such as air control valve malfunction or incorrect fuel mixture.
• Rough idle
• Engine stalling
• Check engine light on
• Faulty idle air control valve
• Vacuum leaks
• Faulty ECM
ECM: Engine Control Module
RPM: Revolutions Per Minute
• Check for vacuum leaks.
• Inspect the idle air control valve.
• Test the ECM for proper operation.
• Replace the idle air control valve.
• Repair any vacuum leaks.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Vacuum gauge
• Multimeter
$150 - $500
Moderate
• Toyota Mirai
• Hyundai Nexo
• Honda Clarity Fuel Cell
• Regular maintenance of the idle air control system
• Ensure no vacuum leaks
• Regular ECM updates
Engine Performance
• Avoid driving until the issue is diagnosed.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code is relatively new and specific to vehicles using hydrogen as a fuel source.
Moderate – It may affect drivability and should be checked soon.
Ignoring this code can lead to increased emissions and potential safety issues.
• Engine at operating temperature
• Vehicle running on hydrogen fuel
The idle air control valve is typically located on the throttle body of the engine.
Q: Can I drive my car with a P108E code?
A: It's not recommended to drive with this code, as it can lead to poor engine performance.
Q: Does this code affect gasoline engines?
A: No, this code specifically relates to hydrogen fuel operation.
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