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Home >> Ford >> 1990 >> Bronco II RWD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Exhaust Gas RECIRCULATION Systems >> EGR Valve (Ported)
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EGR Valve (Ported)

  1. Ensure all vacuum hoses are correctly routed and connected. 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. Remove and plug vacuum hose from EGR valve.
  2. Start engine and idle in Neutral. Note idle speed. Using hand-held 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 step 3. If idle speed does not drop, check for plugged EGR passages or replace EGR valve.
    • If EGR passages are blocked, clean EGR passages.
    • 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 by-pass electrical connector.
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