What Happens When the Idle Motor Fails?
3 Answers
Idle motor is a component that controls the idle speed of a motor vehicle. When the engine is running without load, it is called idling. If the idle motor fails, the following symptoms may occur: 1. The idle speed may be too high or too low. 2. A damaged idle motor can cause the engine speed to fluctuate between high and low. 3. Symptoms of stalling at idle may appear. Information about the idle motor is as follows: 1. The idle stepper motor is mounted on the throttle body and is used by the engine controller to regulate the engine idle speed. When the engine speed deviates from idle, the throttle valve adjusts the amount of air entering the intake manifold, which is mechanically operated by the accelerator pedal cable. 2. The throttle body has a bypass air passage that supplies air during engine idle (when the throttle valve is closed). The pivot of the automatic idle motor extends into the bypass air passage, regulating the air flow. Based on input signals from various sensors, the engine controller adjusts the engine idle speed by moving the pivot of the automatic idle motor in and out of the bypass air passage.
Last time my car's idle speed motor failed, it caused a series of troubles. The engine shook like an earthquake during cold starts, the tachometer needle bounced up and down, and sometimes it would suddenly stall at red lights, nearly causing rear-end collisions. Fuel consumption also skyrocketed, costing me nearly 100 yuan extra per month. Inspection revealed severe carbon buildup in the motor, causing control failure. The repair shop recommended regular cleaning of the throttle body and surrounding components to prevent dirt blockage. While this type of failure is common, it shouldn't be ignored as it may affect other systems like sensor damage. After timely repairs, the car runs smoothly again, making driving much more reassuring.
In the repair field, idle speed motor issues are frequently encountered, mostly caused by dirt accumulation or circuit aging. The motor is responsible for adjusting the air intake during idle. Once it fails, the RPM will fluctuate noticeably, causing significant shaking. During diagnosis, it's best to use an OBD scanner to read the fault codes for confirmation to avoid misjudgment. If it's just dirty, a simple cleaning can restore it. However, if the electrical part is burnt out, a new component must be replaced. If not handled thoroughly, it may also lead to decreased fuel efficiency or excessive emissions, reminding car owners not to overlook minor issues.
