Idle fluctuation: What causes it? How to clean the IAC Valve, also known as the Idle Control Valve. Solution ….. to idle speed problems
The Idle Control Valve is located on the side of your throttle. It regulates how much air enters an engine when it is not in use.
The Idle Control Valve could be blocked by oil and soot deposits if a vehicle is idling irregularly or experiencing fluctuations (idle speeds fluctuate, increase and decrease). In this instance, you should clean the valve using aerosol carbon cleaning sprays. The valve can be cleaned to resolve idle ripple problems.
CAUTION! These operations require some engine knowledge. Do not attempt to modify the engine of your vehicle if you don’t have enough knowledge. You could cause more damage or worsen your own situation.
How do I clean the IAC Valve
- Disconnect the air intake tube from the throttle body.
- Start the engine and increase the idle speed from 1,000 to 1,500 RPM. Hold the button down.
- Spray the special cleaning spray in the throat of your valve and make sure you have it all.
- To allow the cleaning solution to absorb into the throat, stop the engine.
- Give it three minutes.
- Now, start the engine and keep it at 1,000 to 1,500 RPM. Then, clean the engine.
- Restart the engine and reconnect the air intake pipe to your valve body.
- Start the engine, and keep the speed at 1,500 – 2,000 rpm till white smoke is visible from the exhaust pipe.
If that doesn’t work, remove the IAC valve and spray the cleaner directly into your throttle bores using a light wet spray. Continue the process, if necessary. Next, reinstall the IAC Val and start the engine at 1500 to 2000 rpm until there is white smoke coming from the exhaust.
If the ripple problem persists, the IAC valve could be defective and should be replaced.
