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Diesel EGR

WARNING: This page does not describe the selected car, but rather 196 other vehicles, including the 1996 Chevrolet Chevy Van, 1995 Pontiac Trans Sport, 1995 Oldsmobile Silhouette, 1995 GMC Yukon, and 1995 GMC Vandura Special. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn engine off. Disconnect vacuum hose to EGR valve. Connect a hand-held vacuum pump to EGR valve and apply 10 in. Hg. EGR pintle should move up and stay up for at least 20 seconds. If not, replace EGR valve.
  2. To check vacuum pump operation, connect vacuum gauge to vacuum inlet (small fitting). DO NOT plug or disconnect outlet fitting. With engine idling, vacuum should be at least 18 in Hg one minute after start. If not, check for belt slippage, vacuum leaks or other obvious defects. If vacuum reading is as specified, replace EGR valve.
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