Computed Timing Check

Turn ignition off and wait 10 seconds. Using jumper wire or test equipment, activate KOER SELF-TEST. Start engine and check for the following:

• If engine starts and stalls, or stalls during self-test, go to TEST S, step 1).
• If Code 98 or 998 is displayed, it indicates 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 the last service code has been displayed. The timing will remain fixed for 2 minutes after the last code has been received, unless self-test is deactivated.
• Computed timing, at the crankshaft, should equal the 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 TEST PB (vehicles with DIS), or step 2) of TEST PA (vehicles with TFI).