Lean in close loop
Thread Starter
12 Second Club
Joined: Nov 2013
Posts: 69
Likes: 3
From: 45 Mins Below ATL, GA
Lean in close loop My 2002 Trans Am was tuned by a local shop. Everything worked great for about 6 months. Unfortunately my CNC 799 heads dropped a valve seat and need some work. So in the mean time, I reinstalled my stock 853 heads. So pretty much now, I have a Cam only car with all bolt ons.
My wide band show the normal AFRs in open loop, till it goes into closed loop and she want to hanging 15.5 or higher and my wideband doesn’t go above 16.0. And the wideband hit 16.0 plus alot.
Part throttle seems fine bounces in the 14s cruising. WOT is weird. Starts at 12.5 but around 3,000rpm and up, it creep up to 13.3ish.
I have hptuners, and looking for some advice. I did email the tuner; I will see what their response is. But I understand business is business.
I attached a log of me driving around the block. I didnt have my wideband connected.
My wide band show the normal AFRs in open loop, till it goes into closed loop and she want to hanging 15.5 or higher and my wideband doesn’t go above 16.0. And the wideband hit 16.0 plus alot.
Part throttle seems fine bounces in the 14s cruising. WOT is weird. Starts at 12.5 but around 3,000rpm and up, it creep up to 13.3ish.
I have hptuners, and looking for some advice. I did email the tuner; I will see what their response is. But I understand business is business.
I attached a log of me driving around the block. I didnt have my wideband connected.
I'm at work so can't look at your log but if afr's are good in open loop and wacked out in closed loop then you should look at your O2 switch points. Try setting them all at 700 or something just for testing. It should fatten things up. Your WOT afr seems okay. Max torque is achieved around 12.6 and max horsepower is around 13.1 so it makes sense it would trend from 12.5 to 13.3 like that.
