Exhaust Gas Recirculation: Testing and Inspection

To ensure proper operation of the Exhaust Gas Recirculation (EGR) system, all passages and moving parts must be free of deposits that could cause plugging or sticking.

Ensure that the system hoses do not leak.

Replace leaking components.

1. Check the EGR control system and EGR valve with the engine fully warmed up and running [engine coolant temperature over 76° C (170° F)]
2. With the transaxle in neutral and the throttle closed, allow the engine to idle for 70 seconds.
3. Abruptly accelerate the engine to approximately 2000 RPM, but not over 3000 RPM.
4. The EGR valve stem should move when accelerating the engine. Repeat the test several times to confirm movement.
5. If the EGR valve stem moves, the control system is operating normally.
6. Remove the vacuum hose from the EGR valve and plug the hose end.





7. Connect the hand vacuum pump directly to the EGR valve.
8. Check whether the engine stalls or the idling is unstable when a vacuum of 12 kPa (3.5 in.Hg) or higher is applied during idling.