Flow of Diagnosis

THE RELATIONSHIP BETWEEN DTC, MIL AND DRIVING PATTERN
1. When the same malfunction is detected and maintained during two sequential driving cycles, MIL will automatically light.
2. MIL will go off automatically after 3 sequential driving cycles without the same malfunctions.
3. After the ECM first detects a malfunction, a diagnostic trouble code is recorded when the engine is restarted and the same malfunction is re-detected. However, for misfire and CKP sensor, diagnostic trouble codes are recorded on the first detection of the malfunction.
4. After recording the diagnostic trouble code, if the ECM does not re-detect the malfunction 80 warm-up cycles, the diagnostic trouble code will be erased automatically from the ECM memory.

NOTE:
(1) A "warm-up cycle means sufficient vehicle operation such that the coolant temperature has risen by at least 40 degrees Fahrenheit from engine starting and reaches a minimum temperature of 160 degrees Fahrenheit.
(2) A "driving cycle" consists of engine start-up, vehicle operation beyond the beginning of closed loop operation

MFI SYSTEM INSPECTION
If the MFI system components (sensors, ECM, injector, etc.) fail, interruption or failure to supply the proper amount of fuel for various engine operating conditions will result. The following situations may been countered.
1. Engine is hard to start or does not start at all.
2. Unstable idle
3. Poor driveability
If any of the above conditions is noted, first perform an inspection by self-diagnosis and subsequent basic engine checks (ignition system malfunction, incorrect engine adjustment, etc.), and then inspect the MFI system components.