EGR Valve: Testing and Inspection

1. Warm engine to normal operating temperature and check vacuum hoses and pipes for leaks.
2. With engine at idle, check vacuum hose between EGR valve and exhaust manifold for leaks.
3. Disconnect yellow vacuum hose from straight connector on EGR thermo-vacuum switch and connect to T-fitting of hose to intake manifold. (Vacuum can also be supplied with a hand operated vacuum pump).
4. Apply vacuum to the valve.
5. If idle speed decreases, or engine stalls, the system is operating properly. If not, check EGR valve and vacuum hoses for blockage or damage.