Subaru vehicles are known for their impressive performance and reliability. However, like any other vehicle, they require regular maintenance to ensure optimal performance. One component that often goes overlooked is the idle air control valve, which is responsible for regulating the engine’s idle speed.
If you’re experiencing issues with your Subaru’s idle speed, a malfunctioning idle air control valve could be the culprit. In this article, we’ll cover everything you need to know about adjusting the idle air control valve in your Subaru.
What is the idle air control valve and its function?
The idle air control valve is a component of your engine’s air intake system that regulates the amount of air flowing into the engine when the throttle is closed. It does this by adjusting the amount of air that bypasses the main air intake route through the throttle body. This is necessary because when the throttle is closed, the engine needs a small amount of air to run smoothly.
Symptoms of a malfunctioning idle air control valve
A malfunctioning idle air control valve can cause a range of issues, including:
- Rough or erratic idle
- Stalling at idle
- Reduced fuel efficiency
- Inconsistent throttle response
If you’re experiencing any of these symptoms, it’s worth checking the idle air control valve to see if it needs adjusting.
Tools required for adjusting the valve
Adjusting the idle air control valve is a relatively simple process that requires only a few tools:
- Wrench or socket set
Step-by-step guide on how to adjust the valve
Locate the idle air control valve. On most Subaru vehicles, the idle air control valve is located on the throttle body. Refer to your vehicle’s owner’s manual for the exact location.
Disconnect the electrical connector. Use a screwdriver to remove the electrical connector from the idle air control valve.
Remove the valve. Use a wrench or socket set to remove the bolts that hold the valve in place. Be careful not to lose the gasket.
Clean the valve. Use a can of throttle body cleaner to clean the valve thoroughly. Be sure to remove any debris or dirt that may have accumulated on the valve.
Measure the resistance. Using a multimeter, measure the resistance across the two terminals of the valve. The exact resistance values will depend on your specific vehicle, so refer to your vehicle’s manual for the correct values.
Adjust the valve. Use a screwdriver to turn the idle air control valve adjustment screw until the resistance values match the specifications in your vehicle’s manual.
Reinstall the valve. Carefully position the valve and gasket back onto the throttle body. Use a wrench or socket set to tighten the bolts.
Reconnect the electrical connector. Reconnect the electrical connector to the idle air control valve.
Test the idle speed. With the engine running, check the idle speed to ensure that it is within the specified range in your vehicle’s manual. If the idle speed is still not within the specified range, repeat steps 5-8 until it is.
Common mistakes to avoid when adjusting the valve
Here are a few common mistakes to avoid when adjusting the idle air control valve:
- Adjusting the valve without first measuring the resistance.
- Over-tightening the valve, which can damage the valve or throttle body.
- Forgetting to reconnect the electrical connector.
Tips for maintaining the valve
Maintaining your idle air control valve is essential for optimal engine performance. Here are a few tips for keeping your valve in top condition:
- Regularly clean your valve with throttle body cleaner.
- Check the valve’s resistance values periodically.
- If your valve is malfunctioning, consider replacing it with a new one.
Q: Do I need to adjust my idle air control valve if I’m not experiencing any issues?
A: No, if you’re not experiencing any symptoms of a malfunctioning idle air control valve, there’s no need to adjust it.
Q: Can I adjust the valve myself, or should I bring it to a mechanic?
A: Adjusting the idle air control valve is a relatively simple process that can be done by most car owners. However, if you’re not confident in your ability to do so, it’s best to bring it to a professional mechanic.
Q: How often should I clean my idle air control valve?
A: It’s a good idea to clean your valve every time you have your vehicle serviced, or at least once a year. However, if you’re experiencing any symptoms of a malfunctioning valve, clean it immediately.
Adjusting the idle air control valve in your Subaru is a relatively simple process that can save you time and money compared to bringing it to a professional mechanic. By following the steps outlined in this article, you can maintain optimal engine performance and enjoy a smoother, more reliable ride.