Checking the fuel trime value under detecting condition, if its average exceeds the limit over certain period, PCM/ECM sets P0171. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Monitor the fuel trim value | 1. Air leakage 2. Improper fuel pressure 3. PCV valve stuck 4. Clogging of injector |
Enable Conditions |
•
No Failure detection for DTCs | |
Threshold Value |
•
Short term trim value at MAX Limit for more thin 40sec of total monitoring time
•
Short term trim ＞ +50% | |
Diagnostic Time |
•
90 sec. | |
Mil On Condition |
•
2 Drive Cycles |
