So I got two codes one for too lean and another too rich. I know it’s not the gasket for sure and there’s no leaks. Only options I can guess is the o2 sensor.
I know that the fords have 4 sensors two top and two bottom.
Does anyone know which ones are the ones the codes are marking or does one check which is failing?
If it were an exhaust where would it most likely be?
anywhere before the first O2 sensor. Looks for heavy rust.
Also, if it were a gasket the truck would be shooting out white smoke no?
engines have many gaskets
head gasket, yes.
intake gasket, no.
Thanks for the info and help. Turns out it was the O2. Lucky there were no leaks. Nor rust. Gasket also were good .
I know it’s not the gasket for sure and there’s no leaks.
how do you know?
know which ones are the ones the codes are marking
the upstream (before catalytic converter) O2 sensors are the only ones involved in fuel metering.
There's a number of possibilities that can cause this DTC other than O2 sensors though. For you, it's likely an exhaust leak .
https://www.obd-codes.com/p0171
https://www.obd-codes.com/p0175
If it were an exhaust where would it most likely be? Also, if it were a gasket the truck would be shooting out white smoke no?
Does anyone know which ones are the ones the codes are marking or does one check which is failing?
You should be able to check O2 sensor output in live data.
