How to Clean a Dirty EGR Valve

An Easy Repair You Can Do at Home

Clean or Replace Your EGR Valve at Home


If your car is running poorly, you may be having problems with your exhaust gas recirculation valve, or EGR. While you can't test your EGR valve function from home, you can clean it there, a simple task that effectively acts as a repair. There's nothing like turning what could be a very expensive (or at least moderately costly) repair into a home repair victory, and the exhaust gas recirculation valve is easy to access and easy to clean as long as you take a few precautions.

How to Tell If Your EGR Valve Is Bad

Once you have removed your EGR valve, shake it lightly. If you hear something moving back and forth inside, that's the diaphragm—which means there is a good chance that your EGR valve is still good and just needs to be cleaned to return to normal function. If you don't hear anything, your EGR valve might be stuck or it might be bad. Although this is not a foolproof test, it is at least a good starting point.

Before You Clean

If you decide to clean your EGR valve, it's not too difficult. Just make sure that if you're dealing with a newer valve, it is likely to be electronic and therefore will have a wiring harness connected to it. In this case, it is important that you avoid getting corrosive cleaners on the wiring and connectors. It goes without saying that your vehicle's engine should be turned off as well. You'll also need reliable eye protection and chemical-resistant gloves. Then take the following steps below, and you'll likely avoid an expensive visit to your mechanic or service department.

Remove the Vacuum Line

Carefully remove the rubber vacuum line that is connected to your EGR valve. If it is brittle, broken, frayed, damaged in any way, or otherwise seems less than perfect, replace it. Vacuum problems are the source of all kinds of engine woes.

Disconnect the Electrical Harness

If your EGR valve has an electrical connection, carefully disconnect it and lay the wiring aside safely. Again, you want to avoid getting corrosive chemical cleaners like carb cleaner anywhere near the wiring.

Unbolt the EGR Valve

Remove the bolts that attach the EGR valve assembly to the engine. If it doesn't come right off when you have removed the nuts or bolts, it's safe to give a slight tap with a block of wood or a tiny hammer to loosen it.

Remove the Gasket

If your gasket looks okay and isn't torn, frayed, or disintegrated, you can reuse it. If it's questionable, install a new one. We recommend installing a new gasket with any repair.

Soak the EGR Valve

Cleaning the EGR valve assembly is a two-step process. It depends on how far you want to go and how much time you have. First, soak the EGR valve in a bowl filled with carb cleaner. Carb cleaner smells horrible and is nasty stuff, so soak it outside or in a very well-ventilated area. Let it soak overnight if you can. If this isn't possible, skip to the next step. Please note: If your EGR valve has electronic connections on it, do not submerge the electrical portion in cleaner! 

Clean the EGR Valve by Hand

Once you've let your EGR valve soak in cleaner overnight (if possible) you need to clean its passages, openings. and surfaces with a small brush. Toothbrushes and pipe cleaners soaked in carb cleaner work great. When cleaning by hand, be sure to use chemical-resistant gloves and eye protection. Basically, you want to clean everything you can reach with your cleaning brushes. The more black crud you get out of there the better your chances of fixing the problem. 

Reinstall the EGR Valve

Now you can reinstall your clean EGR valve. Don't forget to reattach your vacuum hose and your electrical connections, if applicable. If this process worked, great! If you are still experiencing problems you feel can be traced to the EGR valve, you may have to go ahead and replace it.