Help 02 Sensors Reading 460mv after Maf calibration, wont go back into closed loop

[jerflash]

Hey Everyone,

New to tuning here but have had my 2002 ws6 since new and always had it tuned elsewhere.

Just got the engine back together so before dyno tuning I wanted to make drivability better. It ran good after swapping from an SLP 85mm maf to a z06 screenless 85mm. I was able to put the right maf table in and it started right up and worked everytime. Did some logs with my 02 and saw it was lean pretty much everywhere else besideds WOT. Getting some slight knock down low form this so I know I had to calibrate the maf to my car.

I followed the guide and all was going well until I make the final changes to turn off LTFT and my narrow band 02 sensors stopped reading all together. They just were reading 460mv, stoich, dead in the middle barley moving. I though this was normal since I was forcing it to use the MAF only for all fueling.

After getting the MAf near perfectly dialed in, I reenabled everything and noticed in my logs that the O2 sensors were still not moving and i was not going back into closed loop.

I fiddled with it to see if I missed any settings but nothing. As a last resort I flashed my Known good tune I started the day with and.... same exact thing from the O2 sensors.

Could I have messed something up? I really cant this of anything. Its not my daily drive so i have some time to mess with it but... this is a strange one. especially since I went back to my old tune...

Any help would be great. Here are 3 tunes. First is the known good one, second is The final one i used for maf calibration, third is the calibrated with everything turned back on. Oh also there is a log file to show the 02 sensors not working on the known good tune.

Thanks so much!!!

as found.hpt
MAF Tuning Setup 5.hpt
maf tuning done for now.hpt

[jerflash]

some reason could not upload the log file in first post

thanks again

example log of o2 sensors not working.hpl

[5FDP]

Try going into the scanners special function and enable the LTFT learn, see what happens.

Also you forgot to set the open loop EQ ratio to 1.00 at temps above 130-140 degrees, so your commanded AFR kept changing when it should't be in open loop.

[jerflash]

I see that the fuel system is showing OL-Not Ready. Not sure why that is at all, I have heard of it going into OL-fault but I was not having any issues tuning before I started to make changes and now it is stuck..

Any help would be awesome, still looking on my own but ya...

[jerflash]

Try going into the scanners special function and enable the LTFT learn, see what happens.

Also you forgot to set the open loop EQ ratio to 1.00 at temps above 130-140 degrees, so your commanded AFR kept changing when it should't be in open loop.

Hey Thanks to the quick reply. Where is that that special funtions area, i tried to find it before but no luck.

Also, I did not know you were supposed to set that area to 1.00 above those temps. This was a tune by someone else and I guess it was never changed. Do you have a file with these changes I can checkout before doing it

thanks so much!

[5FDP]

It's the green power button next to the engine icon, you can't miss it.

Look at any truck file from like 2001+, all of those have better open loop EQ ratio tables than the F-body cars.

[jerflash]

Got it thanks! Found the button but does not seem to do anything really. I reloaded the newer maf calibrated tune i did and it just done not run good. waaaayyy to rich because it wont go into closed loop. Kinda of at a loss for tonight...

I will take a look at one of the truck files and paste it in once i get this craziness figured out. I really have no idea what is going on.also ya... that fuel system readiness shit... does that make sense?

[5FDP]

What do you mean the special functions doesn't do anything?

You need to be connected to the car while it's on/running for it show everything. That is where all the fuel system stuff is, like turning on and off the LTFT, resetting it and doing the LTFT learn.

Not having the vehicle in front of me makes it hard to see what is going on. I can't really say much as to why it's doing or not doing something even though the tune file says that closed loop is active.