Datalogged the other day and noticed my Bank 1 & 2 LTFT were off from each other. The SFTF seamed to be about the same but LTFT were off. I had uploade the tune a day or two before logging not sure if the small amount if driving is causing then to be off or not. What is a normal LTFT reading. The log was at WOT not cruising, is LTFT even accounted for at WOT or just cruising?

Can't remember exactly what they were my phone doesn't allow to me to open it, have to wait to get home to open it to post the numbers.

Wayne

 

Long term fuel trim kicks in only after the pcm can't compensate for short term fuel trim. Short term fuel trim is a pre programmed strategy in the pcm to help the fuel mix get where it needs to be when the o2 sensors report an incorrect value,eg: excessive lean or rich mixture.

Long term has no affect when the system is operating properly and is more like a history report on something what happened at some point in time. Ignore it if you are not running bad or have a cel on.