Computed Timing Check

WARNING: This page does not describe the selected car, but rather 15 other vehicles, including the 1992 Mercury Tracer, 1992 Mercury Topaz, 1992 Mercury Sable, 1992 Mercury Grand Marquis, and 1992 Mercury Cougar. However, it is still accessible from the selected car via links, so may be relevant.

Turn ignition off, and wait 10 seconds. Using jumper wire or test equipment, activate KOER SELF-TEST . If engine starts and stalls (or stalls during self-test), go to Circuit Test S. Start engine, and check for following:

If Code 98 or 998 is displayed, EEC-IV system is operating in Failure Mode Effects Management (FMEM). Vehicle cannot be diagnosed in KOER SELF-TEST; rerun KOEO SELF-TEST.
Check computed timing after last service code has been displayed. Timing will remain fixed for 2 minutes after last code has been retrieved unless self-test is deactivated.
Computed timing, at crankshaft, should equal base timing (see vehicle emission decal) plus 20 degrees BTDC. This timing may vary 3 degrees (+/-). If computed timing is within specification, perform KOER SELF-TEST . If timing is not within specification, go to step 2) of CIRCUIT TEST PA (TFI), of CIRCUIT TEST PB (DIS) or of CIRCUIT TEST PC (EDIS).