What Causes Unstable Idle Speed in a New Car?
1 Answers
The reasons for unstable idle speed in a new car are: 1. Air, gasoline vapor, and combustion exhaust entering the intake manifold, causing the mixture to be too rich or too lean; 2. Ignition module failure, incorrect spark plug gap, spark plug electrode erosion or damage, excessive resistance in high-voltage wires; 3. Injector clogging, fuel filter clogging, fuel pump screen clogging, fuel pressure regulator failure, return line clogging, and other faults causing the mixture to be too rich or too lean; 4. Failure or damage of the engine intake system's actuators; 5. Excessive carbon buildup on the throttle and surrounding intake passages, changing the cross-sectional area of the air passage, making it impossible for the control unit to precisely control the idle air intake.