Reasons for Unstable Idle Speed When Air Conditioning is On in Classic Focus
1 Answers
The reasons for unstable idle speed when the air conditioning is on in a Classic Focus are as follows: 1. Reason 1: Poor spark plug performance, where weak sparks from individual cylinders can affect the car's performance. Generally, faulty spark plugs can cause the car to "misfire." 2. Reason 2: Vacuum tube leakage; 3. Reason 3: High-voltage wire leakage; 4. Reason 4: PCV valve blockage; 5. Reason 5: Throttle position sensor malfunction; 6. Reason 6: Idle stepper motor failure; 7. Reason 7: Idle control valve malfunction; 8. Reason 8: Abnormal throttle opening, severe oil accumulation or carbon buildup in the throttle. 9. Reason 9: Intake system leakage, including dirty intake passages, which can make the car difficult to start in cold weather.