How to Adjust the Idle Speed Motor?
2 Answers
Adjusting the idle speed motor involves the following steps: 1. It is best to adjust the idle speed motor when the engine is in a warmed-up state to avoid any impact on the adjustment of the engine speed due to the engine's temperature. 2. After removing the idle speed motor, tighten the conical valve head of the idle speed clockwise until it cannot be turned further. Use a marker to record the position of the valve head at this point, then turn it counterclockwise by 3 turns. 3. Reinstall the idle speed motor, turn the car key to the ON position, wait for 20 seconds, and then start the engine. If the idle speed is normal, the adjustment is correct. 4. If the idle speed is too high, it indicates that the throttle bypass is too large. You need to loosen the idle speed motor valve head counterclockwise by 0.5-1 turns and then repeat step 3. 5. If the idle speed is too low or the engine fails to start, it indicates that the throttle bypass is too small. You need to tighten the idle speed motor clockwise by 0.5-1 turns and then repeat step 3.
As a seasoned driver, I've adjusted the idle speed motor several times myself. Unstable idle speed is usually caused by carbon buildup on the motor, which is located right next to the throttle body and easy to remove. Disconnect the negative battery terminal for safety, then use a wrench or screwdriver to loosen the mounting screws and pull out the motor along with its connector. Spray specialized throttle body cleaner to thoroughly flush away carbon deposits and dissolve residues. After letting it dry for a few minutes, reassemble everything and reconnect the battery. Start the engine and check if the idle speed stabilizes around 700-800 RPM; if it still fluctuates, an ECU reset might be needed - just perform a simple operation with an OBD scan tool. After adjustment, you'll not only save fuel but also prevent sudden stalling when parked, which affects driving safety. Remember to check for carbon buildup monthly to prevent recurrence of the issue.