Symptoms Of A Bad IAC Valve & How To Replace It

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Has your vehicle been idling funny? The trouble could lie with your idle air control valve or the IAC valve, as it is usually referred to by most auto parts stores. The good thing about this issue is that you can replace your IAC valve yourself if this is your problem. 

Diagnosing the IAC Valve

Your IAC valve is an important component of your vehicle that is associated with your throttle. The function of the valve is to make your vehicle idle correctly. The valve does this by simply allowing a specific amount of air into the engine, so that the computer can regulate a specific amount of fuel.

The following are just some ways that you can tell if the issue lies with your IAC valve:

  1. You might notice rough or jerky idling. 
  2. Your car may even stall during idle. 
  3. Pay attention to your vehicle's RPM. Chances are that it drops dramatically during idling or when you are coming to a stop. 
  4. A jerky deceleration is another sign that your IAC valve is dirty, clogged, or completely failing. 
  5. There may be a backfire during deceleration too. 

The reason you want to start with the IAC valve is because it is a relatively easy fix. If you believe that the IAC valve needs to be replaced, you can follow the steps below.

Replacing Your IAC Valve

To replace your IAC valve, you will need the following:

To replace the IAC valve, just follow the steps below:

  1. Let your vehicle cool for at least 20 minutes. Keep your vehicle turned off during this process.
  2. Locate your IAC valve. You can use your vehicle's manual for the exact location. Or, you can talk to your auto parts specialist, as he or she can help you find the location too. The IAC valve is usually shaped like a small "t" and is located towards the back of the intake manifold.
  3. Unplug the wiring harness from the valve. You should be able to see a small tab where the wiring harness connects to the valve. Press on that tab, and unplug the harness.
  4. Use your socket wrench to remove the two bolts securing your valve in place. They are located on opposite sides of each other. 
  5. Simply remove the valve.
  6. Use your throttle cleaner and rag to clean the valve's mount. This should ensure proper installation of your new IAC valve.
  7. Now you just have to bolt down your new IAC valve and connect it. 

As you can see, replacing your IAC valve will not cost you too much. All you need is a little instruction and help from your auto parts specialist. If the problem still occurs, it may be time to go to your mechanic.