EGR Valve: Testing and Inspection

1. Check that valve opens when engine RPM reaches 3000-3500 under no load conditions by observing valve shaft through opening in EGR valve body.
2. If shaft does not move as specified, remove EGR valve and check movement by pressing diaphragm with fingers. Faulty operation may caused by either a damaged diaphragm or a sticking valve shaft. Replace the valve if the diaphragm is damaged or clean it if the shaft is sticking. If cleaning the shaft does not solve the problem, replace the EGR valve.
3. If no fault is found with EGR valve check vacuum lines and fittings.
4. Check EGR pipe and gas passages for clogging and leaks. Clean or replace as necessary.