O2 Sensor Help with HP Tuners!

[My00Z28]

Alright guys well i have been having a problem with my bank 2 sensor 1 O2 sensor. At WOT bank 1 reads 851, and bank 2 reads 56.... im pretty sure this is causing my car to knock on hard pulls... We have been reading all of this on HPTuners also... Any ideas?!

[pajeff02]

Looks like mine did when I accidentally crossed up the left and right senders. One bank went full rich, the other full lean.

[My00Z28]

Ya iv replaced bank 2 already so I'm positive that's not the problem lol

[pajeff02]

Actually, if I recall correctly, at WOT your car shouldn't be running off the O2's -- I believe the PCM reverts to the tables and commands 11.8 AFR or something in that neighborhood. Someone check me on this...

[pajeff02]

What are your STFT's and LTFT's running Bank 1 vs. Bank 2?

[My00Z28]

tested from like 30+ to watch for knock...

[pajeff02]

Swap your O2 senders and see if the problem follows or stays. Even thought it is a new sender it could still be having an issue.

[My00Z28]

I'll try it when I get the chance... It's the second sender on that bank I've had the same problem... It runs good the randomly after a long drive it freaks out saying lean causing my car to run rich as hell and runs like crap.

[pajeff02]

Any chance you have a cracked header and that after it warms up it is sucking outside air into the exhaust?

[My00Z28]

Possible but I would think I would hear it?

[pajeff02]

Hard to tell. Something is causing it to read full lean.

[My00Z28]

ya this has been an on going problem for awhile but first time i had something to review the operation throughout the rpm range...

[Firebirdjones]

Actually, if I recall correctly, at WOT your car shouldn't be running off the O2's -- I believe the PCM reverts to the tables and commands 11.8 AFR or something in that neighborhood. Someone check me on this...

You are correct Jeff, once you hit PE, the 02's are out of the picture.

[Firebirdjones]

I can tell you something similar that happened to me, but it may not be your issue.

My 02 SS was a bone stocker, I thought it was running fine.

My very first mod was to buy Hptuners and tinker. When I started logging the stock tune, my 02's were doing exactly what you are showing, almost like bank 2 wasn't even working. Most of the time it would turn that bar graph red and stay there all the time while cruising around.

I initially thought it was time for a new set of 02's (only had 40,000 miles) so I figured it was time to change them anyway. Put a brand new set in and logged some more. Same thing.

I decided to start tuning it, and started logging all part throttle driving around using 02's (didn't have HPtuner working with my wideband at the time) I logged and logged, filling the VE table using the 02 method. After a couple of days I was happy with what I had and started logging MAF tables in the same manor.

When I was all done, remarkably both 02's started reading nice and steady and nearly mirrored each other on the log. (no more red zones ) My guess is that the factory tune on this particular car wasn't all that great, or didn't agree with something?? But I never had another issue with a non responsive 02 after that on that car. And my gas mileage picked up from 17-18 around town to 20 mpg with simple tuning.

I would assume your car is already tuned though since you have HPtuner...so what I mentioned here may have no affect on your car what so ever. Carry on

[My00Z28]

alright sorry for taking so long to get back but i got the O2 sensors replaced and swapped plugs and wires... so far i have not had a problem but i havent had it hooked up to hp tuners yet....

Thanks for the input guys...