DTC P0171 is set when fuel trim is driven rich beyond a certain value. Possible causes are:
1. Exhaust system leak.
2. Improper fuel pressure.
3. Fuel injector restricted.
4. Defective heated oxygen sensor No. 1.
5. Defective Manifold Absolute Pressure (MAP) sensor.
6. Defective Engine Coolant Temperature (ECT) sensor.
System Too Lean. This code will set when an air fuel ratio sensor (O2 sensor) gets lazy.
Also, check for a vacuum leak on that side.
Hello! Are you located in sub-freezing temperatures? There is a Technical Service Bulletin (TSB) that addresses your vehicle's problem that occurs in cold environment...TSB date; Oct. 27, 2007...P0171 Engine running lean in freezing ambient temperatures...The fix is to replace a leaking intake manifold gasket...Guru....Saailer
I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867
1,490 views
Usually answered in minutes!
×