DTC P0171 System Too Lean (Bank 1): DTC Detecting Condition

DTC DETECTING CONDITION AND POSSIBLE CAUSES

Item		Detecting Condition	Possible Cause
DTC Strategy		Long-term fuel trim limit	Poor connection Related sensor Intake air system Fuel pressure ECM/PCM
General Enable Conditions		Coolant temperature > 70°C (158°F) Intake air temperature < 80°C (176°F) Throttle angle < 60% Closed loop control enabled No transient control phase No canister purge phase
Case1	Enable Conditions	Engine load: 30~75 % Air mass: 40~200 kg/h (88.2~441 lb/h)
	Threshold Value	Multiplicative > 1.23
	Diagnostic Time	30 sec
Case2	Enable Conditions	Engine speed ≤ 920 rpm Air mass ≤ 24 kg/h (53 lb/h)
	Threshold Value	Additive value > 8.5 %
	Diagnostic Time	20 sec
MIL ON Condition		2 driving cycle