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Forcefedperformance
June 23rd, 2009, 04:14 AM
We did some VE tuning last night on a 02 Z06 and got it just about spot on....we let it cool down for about a hour and it was about 4% rich, pulled some more fuel and called it a night. This morning we fire the car up and let it warm up and its 6-13 % rich ...i have Looked over the file countless times and i cant figure out was is going on...Can someone look at this file and see if there is something we are overlooking?

02 Z06 6.2 P1SC procharger

Bill

GMPX
June 24th, 2009, 06:43 PM
I'd suggest it has to do with tables A0014 & A0008.
As they are both set to 1.00 everywhere you have no mixture compensation for intake or coolant temps.
Assume you tuned it when the intake temps were up (say 115degF), then when you start the car the next day and the IAT's are 70 it will throw things out.

Now by no means is what I changed in those two tables is going to be spot on, but it might pull everything in to line or at least demonstrate what direction you need to be heading in with those tables.

Cheers,
Ross

Forcefedperformance
June 29th, 2009, 02:47 AM
I see where you were going with those 2 tables but that did not solve my problem... I reset those tables back to 1.00 And let the car warm up, Watched my air temp rise from 75 to 105 with no change in air fuel...Again i pulled more fuel from the file...Got my air fuel 14.7 to 15.1...Let the car set over the weekend....came in this morning started the car and let it warm up and my air fuel is back to 13.2 with the same air temp and the same coolant temp....Any other ideas????


Bill

98 tigershark
August 24th, 2009, 06:13 PM
Some times when I put a new tune it does not take in the PCM and a reduced power mode takes place. There are no dtc's to know this. But when you flash the car do you have an led readout below the speedo?
If so make sure that the SES or reduced power mode is not active. As soon as it is done flashing look at the readout before you turn the key off. Sometimes reflashing it a time or two can do it. If not the only other thing I can think of is a fouled O2 sensor, a loose belt, intake air leak somewhere, or an exhaust leak. Does the O2 sensor warmup? Sometimes that is an easy way to know but it still can be fowled. Is it that way on both sides?
Let me know,
98 tigershark