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Home >> Ford >> 1990 >> Bronco II 4WD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Quick Test >> Step 5.0 Perform Engine Running (KOER) Self-Test >> Begin
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Step 5.0 Perform Engine Running (KOER) Self-Test: Begin

Deactivate Self-Test. Start engine and idle until vehicle is at operating temperature. Run engine for 2 more minutes at 2000 RPM to warm-up EGO sensor. Turn engine off and wait 10 seconds. Activate Self-Test (same as before). Start engine.

NOTE: If engine starts and stalls, or stalls during self-test, go to TEST S - SYSTEM CHECK , step 1).

Record all service codes displayed. Watch for the Engine Identification codes (ID codes), because a response to the ID code is required for some vehicles:

Next, watch for a possible Dynamic Response Code. The signal is a single pulse or 10 code on the STAR Tester. If it occurs, perform a brief Wide-Open Throttle (WOT).

Is a PASS Code "11" received during the Engine Running Self-Test?