Originally Posted by
Jay@HAP
Can you post a log?
The reason for this histo is this. At each Fuel Mass breakpoint there is an InjPW value. The PCM looks at the tune to achieve a particular Fuel Mass, then looks at the 02 sensor to see how it did.
If the 02 sensor says, hey we needed another +20% of in the fuel trims to get the Fuel Mass you asked for originally, you can record it in the histo.
It's just like using STFT for VE tuning, same was using STFT for MAF tuning.
Dodge is a little different you can only do STFT/LTFT except for the Cats where you can use STFT at WOT tuning.
Post your log, there's probably something really simple that needs to be changed in your histo. Once you see the histo working it will make a lot more sense.