Closed loop fuel trims

[CoreyB]

That is my point, with the engine OFF I am seeing IDC's for the front bank. They start at about 4% and climb the longer I log.
The STFT and LTFT start near zero and move toward max negative -25. Again with the engine OFF.

The rear bank is doing what it should, all zeros. So upon investigation I noticed the front O2 is reporting a voltage or the ECU is seeing a voltage for the front O2. My theory is this is the problem causing the.IDCs and crazy fuel trims on the front back. I still need to track this further down.
Did it make more sense this time?

[CoreyB]

My bad guys, the IDCs are zero when not running. Its the front bank pulse width that slowly rises to just over 22 ms. Still doesnt make a bit of sense. I cannot get the front trims to zero out, they always go right to or very close to -25.
At this point I dont 100% trust the logger. The car runs too good for these numbers to be real. I am confused.

[RealMcCoy]

I would also suspect the logger... I think all the info you're seeing for the front bank is garbage.

I see you are using the Chrome Evoscan file, Are you using a flash ECU with Chrome?

[CoreyB]

Using the chrome setup file for evoscan, stock 92 TT ECU. I am using a 1.3 cable and the MMC 1G connection.

[RealMcCoy]

I would say that's the problem... There are several parts of that file that are designed to work only with Chrome. You will get bad data in some areas if used with stock ECU.

Evoscan in general is pretty weak on earlier cars... I use Hand Held Halo for PC, or a Palm and MMcd.

[CoreyB]

Ok man, thanks for the reassurance.

[KeithMac]

Palm and MMCD has always been fine on my 1st Gen.

[striker2]

FWIW, I see some voltage on the front O2 sensor with the KOEO as well. Im running a 99 ECU with Chrome and I see it both with EvoScan and the tactrix logging so I know its not the logger. havent tried unplugging the sensor yet to see if the voltage goes to zero though.

[CoreyB]

The voltage from the O2 proved to not be the issue. I unplugged all kinds of shit and still saw 22 ms of IPW without even running. in closed loop my front IPW is always 12-13 ms higher than the rear. When I go to open loop they even out.
I even connected the front O2 to the the rear O2 harness and nothing changed.