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EGR Valve (Ported)

  1. Ensure all vacuum hoses are correctly routed and securely attached. Replace any crimped or broken hoses. Ensure there is no vacuum to EGR valve at idle. Install tachometer. Disconnect idle air by-pass valve electrical connector (EFI only). Remove and plug vacuum hose from EGR valve.
  2. Start engine and idle in neutral. Note idle speed. Using hand vacuum pump, slowly apply 5-10 in. Hg of vacuum to EGR valve. When vacuum is fully applied to EGR valve:
    • If idle speed drops more than 100 RPM or if engine stalls, perform next step. If idle speed does not drop, replace EGR valve.
    • If EGR passages are blocked, clean EGR valve.
    • Remove vacuum from EGR valve. If idle speed does not return to normal, check for contamination, clean valve.
    • Ensure no contamination or debris is left in valve or pick-up tube. Replace valve if necessary.
  3. Unplug reconnect EGR vacuum hose. Reconnect idle air bypass electrical connector.
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