Without Modulator Or With BACKPRESSURE Transducer
- Check vacuum lines for correct routing. Disconnect vacuum hose at EGR valve and plug hose end. Connect vacuum pump to EGR valve. Start engine. Apply 6-10 in. Hg to EGR valve and hold.
- Engine speed should drop at least 100 RPM or stall. Vacuum should not drop more than 1 in. Hg in 30 seconds. Reconnect EGR vacuum hose.