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 running faster than it should when it's just sitting still.
The P108F code indicates that the engine's idle speed is higher than what the engine control module (ECM) expects during H2 operation.
The idle air control system is responsible for maintaining the engine's idle speed. When the engine is idling, the ECM uses the idle air control valve to regulate the amount of air entering the engine to maintain a steady RPM. If the RPM is higher than expected, it could indicate a problem with the idle air control system or an air leak.
• High idle RPM
• Check engine light on
• Rough idle
• Faulty idle air control valve
• Vacuum leak
• Dirty throttle body
ECM: Engine Control Module
RPM: Revolutions Per Minute
• Check for vacuum leaks.
• Inspect the idle air control valve.
• Clean the throttle body.
• Replace the idle air control valve.
• Repair any vacuum leaks.
• Clean or replace the throttle body.
• OBD-II scanner
• Vacuum gauge
• Throttle body cleaner
$100 - $300
Moderate
• Chevrolet HHR
• Toyota Prius
• Ford F-150
• Regular maintenance of the throttle body.
• Check for vacuum leaks periodically.
• Ensure proper idle air control valve operation.
Engine Performance
• Do not ignore the check engine light.
• Have the vehicle inspected by a professional if unsure.
• Regularly maintain your vehicle to prevent such issues.
Check with your vehicle manufacturer for warranty coverage on engine components.
The P108F code has been reported in vehicles with idle control issues, often related to air intake or control valve problems.
Moderate – While the vehicle may still operate, ignoring the issue can lead to poor fuel efficiency and potential engine damage.
Driving with a check engine light can lead to increased emissions and may be illegal in some areas.
• Engine at operating temperature
• Vehicle in idle state
The idle air control valve is typically located on or near the throttle body of the engine.
Q: Can I drive with a P108F code?
A: It's possible, but not recommended as it can lead to further engine issues.
Q: How can I reset the check engine light?
A: You can use an OBD-II scanner to clear the code, but it may return if the issue is not fixed.
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