The idle air control valve is a small, yet important component in your car’s engine. Its job is to regulate the air flow into your engine, which in turn controls the engine’s idle speed.
When functioning properly, it helps maintain a steady idle speed under various conditions. However, a dirty or faulty idle air control valve can lead to rough idling and other engine issues. Regular testing and cleaning of this valve can help prevent these problems.
This guide will walk you through the process of testing and cleaning your idle air control valve, along with other important information to help you maintain this component.
How will you know whether your idle air control valve is dirty or not working altogether? Well, you can use a multimeter to determine whether the valve is working.
If the test shows that it is working, then it means your valve is simply dirty. But if the test shows the valve is not working, then you need to replace your valve.
The tools and accessories you will need to do the test include a screwdriver, multimeter, socket wrench, electronic parts cleaner, and likely a 10mm socket.
Test and Clean Procedure
- Open the hood of your vehicle. Locate the idle air control valve behind the engine and unscrew it from the throttle body.
- Disconnect the electrical plug from the control valve. If there’s a release tab on top, squeeze it as you pull.
- Remove the idle control valve and flip it over to expose the valve openings.
- Take your multimeter and set it to “Ohms.”
- Touch one multimeter lead to one end of the valve terminal, and the other lead to the opposite end. A reading between 0.00 and 0.05 ohms is normal. Any reading outside this range indicates a faulty valve.
- If the reading is normal, inspect the valve openings for dirt. Some dirt on the sensor is expected if the valve is functional.
- To clean, spray an electronic parts cleaner solution onto the valve’s sensor. Allow the fluid to drain through the valve openings.
- Wait for the sensor to dry completely. Once dry, reattach the valve to the throttle body by reversing steps 3 through 1.
When to Test Your Idle Air Control Valve
Regular testing of your idle air control valve can help prevent engine performance issues. Here are some guidelines on when to test:
- During routine maintenance. Consider testing your idle air control valve every 60,000 to 100,000 miles as part of your regular vehicle maintenance schedule.
- When you notice irregular idling. If your engine idles roughly, stalls frequently when stopped, or has inconsistent RPMs at idle, it’s time to test the valve.
- After cleaning the throttle body. Since the idle air control valve is closely related to the throttle body, it’s a good idea to test it after cleaning the throttle body.
- Before emissions testing. A properly functioning idle air control valve can help your vehicle pass emissions tests more easily.
- Before winter. Cold weather can exacerbate issues with the idle air control valve, so testing before winter is advisable.
- After long periods of inactivity. If your car has been sitting unused for an extended period, testing the valve before returning to regular use is recommended.
Safety Precautions
Before testing or cleaning your idle air control valve, there are some important safety guidelines you should follow.
- As with any engine work, make sure the engine is completely cool before you start. Working on a hot engine can lead to burns.
- Park your vehicle on a flat, stable surface. Engage the parking brake.
- To prevent electrical shocks or short circuits, disconnect the negative terminal (has a “–” symbol) of the battery before working on electrical components.
- Work in a well-ventilated area, especially when using cleaning solvents. Avoid inhaling fumes.
- Use the right tools for the job to avoid damaging components or injuring yourself. Can’t find your 10mm socket? Don’t get too creative using a substitute.
- Always refer to your vehicle’s service manual for specific instructions and precautions related to your make and model. YouTube and automotive forums are a good resource as well.
- It should go without saying but if you’re a smoker, don’t smoke near the vehicle while working, as fuel vapors may be present.
- Immediately clean any spilled fluids to prevent slips and falls.
- Know your limits! If you’re unsure about any step in the process, it’s best to let an actual mechanic work on it rather than risk damage to your vehicle or personal injury.
Alternative Testing Methods
If you don’t have access to a multimeter, there are other ways to assess your idle air control valve’s condition.
One simple method is to start your engine and let it idle. Then, quickly tap the gas pedal to rev the engine. If the idle air control valve is working properly, the engine should quickly return to a steady idle. If it doesn’t, or if the idle is erratic, this could indicate a problem with the valve.
Another approach is to listen for unusual sounds. A failing idle air control valve may produce a distinct clicking or buzzing noise. You can also try unplugging the idle air control valve while the engine is idling. If the engine’s RPM doesn’t change, this suggests the valve may not be functioning correctly.
Visual inspection can be helpful too. Remove the valve and check for carbon buildup or damage. If you see significant deposits or any physical damage, cleaning or replacement may be necessary.
Keep in mind that while these methods can give you an idea of your valve’s condition, they’re not as precise as using a multimeter.
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Can the idle control valve prevent my kia soul from strating but start only when i press down on the excellarator
I doubt it. I would expect a failing idle air control valve to let your engine start, then immediately die when the car couldn’t hold idle.
Have you tried scanning for codes yet?
I have a 1997 Nissan pickup it has a high idle of sometime 2000 rpm. I ohms the valve it read 9.9 ohms.
Have you tested for vacuum leaks?
Could I use mass air flow sensor cleaner to clean this part? The car ran fine til I replaced the abs control module and I cleaned the engine with some exterior cleaner made for cars. I’m thinking I may have messed up and gotten some into this part by accident.