Strong gas smell when starting

Originally Posted by Jhill

All cars use the AF sensors for fuel trim. The mafs + rpm determine what cell on the map the car is in and the AF sensors give the feedback to verify the AF is matching the desired AF. What I was talking about was Nissan in the oem data does not list or use stft or ltft it uses that alpha data, something a bit foreign to me but I guess it’s like a combo of both.



Can’t say for Nissan but in my experience AF sensors don’t “age” and get lazy like a classic o2 sensor. If it’s way off you can use the rear o2 vs front AF readings to see if something is up.