If the lambda controller reaches the maximum or minimum threshold, then feedback control is no longer possible and emissions will be increased. The ECM sets DTC P2188 if no proportional post catalyst fuel trim adaptation occurs for a defined time after the lambda controller has reached its minimum threshold at idle.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Additive long term fuel trim upper limit monitoring | 1. Poor connector connection 2. Air leakage in intake or exhaust system 3. Improper fuel pressure 4. Stuck PCV valve 5. Clooged injector |
General Enable Condition |
•
Coolant temperature is higher than 80.3℃(176.54℉)
•
Intake air temperature is lower than 80.3℃(176.54℉)
•
Lambda feedback control condition - active
•
Purge valve control duty is 0%
•
No MAP sensor error
•
No CVVT system error
•
No ATS error
•
No PCV error
•
No ECTS error | |
Enable Condition |
•
Engine torque is at between 5.0% and 30% | |
Threshold Value |
•
Long term fuel trim (Additive) is lower than -9.0% | |
Diagnostic Time |
•
25 sec. | |
MIL ON Condition |
•
3 driving cycles |
