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Diesel EGR (1982-89)

WARNING: This page is about a different variant/trim than selected.
  1. Warm engine to normal operating temperature. Remove air cleaner cover to observe operation of EGR valve. With engine at idle, EGR valve should be open. If valve is not open, check and correct any electrical and hose connection which may be loose or disconnected.
  2. Disconnect vacuum hose from EGR valve. EGR valve head should drop with noticeable reduction in noise. If EGR valve does not operate as specified, clean or replace EGR valve as necessary. Reconnect vacuum hose.
  3. With engine at idle, vacuum hose to EGR valve should have at least 20 in. Hg. If vacuum is not present, check output to vacuum pump at pump. Pump should produce a minimum of 20 in. Hg.
  4. Turn engine off. Disconnect vacuum hose to EGR valve. Connect vacuum pump to EGR valve and apply 10 in. Hg. EGR valve should move up and stay up for at least 20 seconds. If not, replace EGR valve.
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