If your car's engine is idling roughly, has lost power or its fuel economy has noticeably dropped, it’s possible you have a sticking EGR valve. While an EGR valve is not repairable due to its sealed construction and use of a vacuum diaphragm, a sticking EGR valve can sometimes be returned to proper working condition with a thorough cleaning. If it is not sticking, periodic cleaning can extend its life.
Locate the EGR, or exhaust gas recirculation, valve on the engine. It will be a flattened round device, usually mounted on the side of the engine on the intake manifold, or on the end of a tube. It can sometimes be located at the rear of the engine, mounted on a long tube. It will have one or more vacuum hoses attached to it, and if it is electrically operated or controlled, it will have one or more wires also connected.
Place the vehicle in park, set the emergency brake, raise the hood, and start the engine. Allow the engine to reach operating temperature, Rev the engine a few times and watch the EGR valve's plunger. If it does not move at all when you rev the engine, the valve is defective and should be replaced. If the valve operates and the plunger arm moves when you rev the engine, proceed with cleaning the valve.
Mark all hoses and wires connected to the EGR valve with pieces of masking tape and a pen for later reinstallation.
Pull the hoses off the valve, and disconnect any wires. Inspect all the hoses and wires that come off the valve for cracks or holes. If you find cracks or defects in the hoses or wiring, they will need to be replaced.
Use the socket wrench to loosen the bolts that hold the valve to the intake manifold and remove them. If the valve is mounted on a tube, remove the bolts that hold the tube to the engine. Pull the valve from the engine.
Use a small wire brush to scrub off deposits from around the openings in the valve and tube, if it is so equipped.
Spray carburetor cleaner into the openings that mate to the engine and exhaust ports, making sure to thoroughly soak the openings, and allow any excess cleaner to run off, taking the removed deposits with it. If the valve is not electronic, it can be soaked in a pail with parts cleaner for 30 minutes instead.
Wipe the EGR valve off with a clean rag and it to dry thoroughly. Reinstall the EGR valve in the reverse order of removal.
