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.
Post the tune and a log with the wideband logged.
The log you posted shows LTFT to be ok. low single digits -1-5.
At 100% TPS your O2 voltages are 900mv which it should be.
The wideband should closely follow the commanded AFR at idle/ part throttle/ cruise.
Ex. 14.6 AFR the W/B should vary between 14-15 AFR.
At WOT, it should match the commanded P/E.
Just a basic explanation. That I`m sure someone will correct if needed.
This is without the fuel adders,etc.
Don't have access to laptop at the moment but where are you getting your wideband readings from? Tail pipe sniffer or exhaust bung?
If it's a sniffer in the tail pipe it will be useless at part throttle for afrs, ones I've seen read, . 5 to 2 leaner afrs at the sniffer with light driving.
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