Diagnostic Procedure

NOTE: DO NOT skip any steps in self-diagnostic tests or incorrect diagnosis may result.

Always perform a visual inspection before attempting to diagnose engine control system problems. See VISUAL INSPECTION . Enter on-board diagnostics, and retrieve Diagnostic Trouble Codes (DTCs). See ENTERING ON-BOARD DIAGNOSTICS . If DTCs are not present and/or scan tool is used, proceed to one of the following tests:

Go to TEST NS-1A , QUALIFYING NO-START CONDITION, if a no-start condition exists or engine stalls after start-up. Perform indicated VERIFICATION TEST after repairs have been made.
Go to TEST TC-1A , CHECKING FOR DTCs, if engine runs but has performance problems. Perform indicated VERIFICATION TEST after repairs have been made.
Go to TEST NTC-1A , NO DTC TEST MENU, if a driveability problem exits and no DTCs are present. Perform indicated VERIFICATION TEST after repairs have been made.