Very interesting front O2 readings, Check out my log please

[90peeclipseGSTurbo]

3" GM MAF, 740cc injectors, running off of stock O2 sensor ATM.

I'll upload 2 datalogs from V3 ECMLink. if you look at the O2 sensor reading it seems that it tries to cycle normally, although there are very jagged peaks and valleys in the sweep.

I ended up replacing the the O2 sensor and it seemed to help a bit, but it still isn't smooth. My tune is a little on the fritz, and I am trying to dial in my fuel trims, but the car doesn't seem to be behaving. If you look through the logs, when I start driving and the engine has a load on it the readings seem to be normal. Check it out, and tell me what ya think. Thanks!

 

[punk3rz]

I'm on my phone so I can't view the logs but if you're at idle in closed loop, your o2 sensor should cycle up and down (.2-.8ish volts). Once you start moving, you will go into open loop and your o2 sensor should move normal. I'll check back later when I'm on my computer to confirm.

 

[curt-s]

You will only transition to open loop if you exceed a throttle position or load threshold. Normal cruise and most normal/sane driving behaviors will keep you in closed loop and your NB O2 will only cycle in that mode. Unsure what "move normal" means.

 

[90peeclipseGSTurbo]

I'm on my phone so I can't view the logs but if you're at idle in closed loop, your o2 sensor should cycle up and down (.2-.8ish volts). Once you start moving, you will go into open loop and your o2 sensor should move normal. I'll check back later when I'm on my computer to confirm.

Any input would be appreciated. Ueah i understand closed and open loop a little better. There are definitely issues in closed loop as open loop seem fine.

 

[90peeclipseGSTurbo]

You will only transition to open loop if you exceed a throttle position or load threshold. Normal cruise and most normal/sane driving behaviors will keep you in closed loop and your NB O2 will only cycle in that mode. Unsure what "move normal" means.

When I say normal, I mean the up and down sweep of the O2 sensor voltage. It's all out of whack in closed loop.

 

[curt-s]

Sorry I was responding to punk3rz's "move normal" comment and cautioning that just because you start moving, it doesnt necessarily mean you will move to open loop immediately. There are one of the two aforementioned thresholds that must first be crossed (viewable in the DA section)