EGR Valve: Testing and Inspection

Fig. 7 EGR valve.:

1. The EGR valve, Fig. 7, should meter a small amount of exhaust gas into the intake system when vacuum is applied. To test the EGR valve function, proceed as follows:
a. With the engine fully warmed-up, apply vacuum to the EGR valve with a suitable hand-held vacuum pump with a built in gauge.
b. The engine should stumble or die and the EGR valve should hold vacuum.
c. If the valve holds vacuum but the engine does not stumble, remove the valve and check for clogged EGR passages or a damaged valve pintle. Clean or repair as necessary.
d. If the valve does not hold vacuum, it must be replaced.