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Home >> Lincoln >> 1987 >> Mark VII Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (2.3L HSC/CFI Testing) >> Quick Test >> Key On/Engine Running (KOER) Self-Test >> Code Output
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Code Output

WARNING: This page is about a different car, the 1987 Mercury Topaz and 1987 Ford Tempo. However, it is still accessible from the selected car via links, so may be relevant.
  1. Deactivate SELF-TEST (disconnect jumper wire). Start engine and run it at 2000 RPM for 2 minutes to warm up HEGO sensor. Turn engine off and wait 10 seconds
  2. Start engine. Insert jumper to activate SELF-TEST. The engine ID code will be displayed. On vehicles equipped with the 2.3L HSC/CFI engine, the steering wheel MUST be turned one-half a turn and released AFTER the ID code.
  3. If a Dynamic Response code occurs, briefly accelerate engine to wide open throttle (WOT). DO NOT depress throttle during test unless a Dynamic Response code occurs. The KEY ON/ENGINE RUNNING (KOER) SELF-TEST service codes will then be displayed. Observe and record all codes.
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