EGR Valve With Integral BACKPRESSURE Transducer

1. Check that all vacuum hoses are properly routed, all connections are secure, and that vacuum hoses are not cracked, crimped or broken. Ensure no vacuum is present at EGR valve at idle and engine is at normal operating temperature. Disconnect air by-pass valve connnector.
2. Connect tachometer to engine. Plug exhaust tailpipe(s) to increase exhaust backpressure, leaving 1/2" diameter opening to allow exhaust gases to escape. Remove vacuum hose to EGR valve and plug hose.
3. Start engine, idle with transmission in Neutral. Note idle speed and adjust if necessary. Using vacuum pump, slowly apply 5-10 in. Hg vacuum to EGR valve vacuum nipple.
4. Replace EGR valve, if engine does not stall, idle speed does not drop greater than 100 RPM or idle speed does not return to normal (plus or minus 25 RPM) after vacuum is removed from valve.
5. If EGR valve is good, reconnect idle air by-pass valve connector. Reconnect vacuum hose and remove tailpipe(s) plug(s). Valve cannot be opened by vacuum until bleed hole is closed by exhaust backpressure.

Fig 1: EGR Valve With Integral Backpressure Transducer

Courtesy of FORD MOTOR CO.