Learning About Auto Service Procedures

If your vehicle stalls, the check engine light comes on, or it has trouble idling, the EGR valve may need cleaning. The EGR valve, or the Exhaust Gas Recirculation valve, pulls a small amount of exhaust so it recirculates into the engine to reduce  emissions from nitrogen oxide. 

However, this constant process often causes carbon build up, which interferes with operation. Clean the EGR valve by following these steps.

Prepare to Clean the EGR Valve

To clean the EGR valve, gather:

• rubber gloves
• safety glasses
• socket ratchet set
• screwdrivers
• needle-nose pliers
• rags pipe cleaner or small brush
• lubricant
• electrical cleaner 
• carburetor cleaner 

Shut off the engine, and let it cool. Raise the hood, and disconnect the negative battery cable. Look for the valve, commonly located on top of the throttle body or exhaust intake manifold, or refer to your manual. Valves may be manual or electrical.

Remove the EGR Valve

Some EGR valves may have a vacuum hose attached to the valve. Remove the hose from the connectors, and use the correct socket and ratchet to remove the two to four mounting bolts on the valve. If the valve is electrical, take note of the wiring or label the wires.

Spray lubricant on bolts that are hard to remove, let it stand several minutes, and try again. If the valve connects to a pipe, remove the pipe with a crescent wrench. Lift the gasket from the manifold, and check the gasket on the bottom for damage. Undamaged gaskets can be reused.

Clean the EGR Valve

Inspect the hose for cracks, holes, hardening and softening, and replace damaged hoses. If the hose is still in good condition, spray the inside with carburetor cleaner, and scrape the inside using the pipe cleaner. Use the brush to clean hardened deposits on the outside.

Set the valve on a clean rag, and wipe the motor, plastic parts, and solenoids. Don't clean these parts with the carburetor cleaner. 

Spray some cleaner on the valve cover, the gasket, and inside the ports and the valve. Scrape the debris, cleaning spills on plastic or electrical parts with rags. Ensure the remnants of =damaged gaskets don't fall into the holes. If the grime is stubborn, let the valve soak for two to three hours. 

The metering rod must work properly. Test the rod for smooth operation by pushing a screwdriver tip on the rod. The valve is properly cleaned if the rod moves freely. Reinstall all parts, replacing damaged gaskets, and reconnect the battery cable. Contact a shop, like Lamb's Automotive Repair with Care, for more help.