jchapura

I recently changed my fuel injectors on my 997.1 because I thought they might be contributing to fuel-in-the-oil.

Is there a way to reset the LTFT Long Term Fuel Trim to force it to start learning the new values immediately? If there's no way to reset the LTFT, does anyone know how long (miles or hours) it will take for it to optimize itself after this major fuel delivery change?

Petza914

Disconnecting the battery for 10 minutes should do it. I think with a scan tool if you click "clear all faults" it will do it also. If I do this with my car I have to do it running or it's almost impossible to restart once it clears the learned data. If I do it running, it stumbles, recovers, relearns and smooths back out.

jchapura

Thanks Pete.
I disconnected the battery before starting the job - it did take a lot of cranking to get the thing started but I thought it was having to fill up the fuel rails. The idle definitely changed character in those first few minutes.