I have been running my 99 C5 (422 ci, 540 rwhp) with custom OS 3 in a 2001 software base. I did the AutoVE tuning on the car and decided to leave it in SD mode (nice to not have the MAF in the intake). This is a dedicated race car. The car runs great and makes great power, but has some odd driveability and idle issues.

I didn't make any changes to the software to return it to 'functional' after the VE tuning. Are there any fuel trims that need turned back on or any other features that I need to re-enable?

One of the annoying symptoms I have is that the car will start right up at crank, and idle perfectly. After about 1 to 2 minutes, it shuts off like someone turned the key. It also will not return to idle from a free rev, it stalls almost every time. I can make the idle better or worse with the airflow tables, but never make it return to idle. I have a friend with the same cam that uses all the 01 Z06 cals (same base cal as me) in the idle and has no problems with idle. This has the 90mm TB (as does my friends car).

Another question is, how do I do the crank learn? I have no codes other than that and the learn procedure button is still greyed out in the toolbar. Not all that important, but just wondering if that could cause any of my problems.

Any help is appreciated.

thanks,
Aaron Pfadt
Pfadt Race Engineering
1525 S. Gladiola Rd.
Unit #1
Salt Lake City, UT 84104
888-972-2464
801-386-5148 fax
aaron@pfadtracing.com
www.pfadtracing.com