How to Clean EGR Valves

EGR stands for Exhaust Gas Recirculation. The EGR valve is designed to redirect some of the engine's exhaust into the engine's intake manifold, which cools down the air inside the engine and helps reduce nitrogen gas emissions. Over time, this valve can become gunky and sticky, causing a buildup of nitrogen gases. This may cause the vehicle to fail required emissions testing or to start lurching during steady acceleration.

Things You'll Need

  • Socket wrench set
  • Flashlight
  • Repair or owner's manual
  • Carburetor cleaner
  • Rag
  • Small wire brush
  • Find the EGR valve (see photo). It is usually located on top of or in the back of the engine's intake manifold. If necessary, refer to the repair or owner's manual for your car to locate this part.

    Typical EGR valve
  • Examine the EGR valve carefully, paying particular attention to the location, number and type of bolts used to hold it in place. This varies from one car to the next, and on some cars it may be difficult to reach these bolts. They can usually be removed with a socket wrench and the right size attachment.

  • Pull the EGR valve off of the manifold after removing the bolts. Turn it upside down. On the bottom, you will see an open hole and another hole covered by some type of movable cover. The covered hole is the actual valve. Push this cover into the body of the valve housing by pushing it with your finger or the tip of a wire brush. When you release it, the cover should spring right back down into place. If this movement is sticky at all, the valve should be cleaned until it moves smoothly and easily.

  • Spray some carburetor cleaner onto the valve cover and inside the valve itself, but make sure not to spray onto or into any other parts of the valve housing. As you spray the valve, clean away the loosened gunk with a rag and wire brush. Keep working on the sticky buildup until the valve moves smoothly.

  • Look at the top of the engine intake manifold where the EGR valve was installed. You should see two small holes under the valve mount. Spray a little carburetor cleaner into each of these holes and wipe them clean with the rag.

  • Reinstall the cleaned EGR valve using the tools you used to remove it. Make sure the bolts are fully tightened.