I have a 2000 ranger with the 2.5 4cyl and my CEL turned on while accelerating to 70 mph on the highway. Pulled the code P0171 running too lean at AutoZone. Cleaned the MAF sensor, replaced fuel filter, and disconnected the battery to reset the code. The light didn't come back on for a while. It turned on again after a pretty long time. Maybe an 02 sensor is bad? Any thoughts?
Yea check the o2 sensor and get the fuel system pressure tested and try and get someone with a good scan tool to scan it and see how low the fuel trim is.
Hello,
This model is prone to PCV valve failure,
So the first thing to do is check your PCV valve and line.
I've included a link for your information.
All the Best.
Link:- https://www.700r4transmissionhq.com/p0171-ford-ranger/
