starshifter

I am working with a friend to tune my 99 Corvette hardtop. He has EFIlive. First he changed my ignition and AFR tables and everything went fine. He then changed the PCM's OS to 2003 and accounted for the fact that I have 26#/hr injectors and a 74mm MAF (since these parameters changed in 2001). We went for a test drive with the 2003 OS while he was logging data. Everything seemed fine at first until the fuel suddenly cut off while I was cruising in 6th at about 70MPH. I give it gas, but fuel is still cutoff. The only way to get the injectors to open is to downshift. As soon as I'm in 5th the car starts responding to my throttle input. The same thing happened again a dozen times while we were testing. He tried to change the DEFCO settings a few times but that did not resolve the issue. He then got me back to the 99 OS and the problem went away. Can anybody tell me what is going on? I'd really like to upgrade the OS to the latest year that would be compatible. Please help.

joecar

Also try posting here: http://forum.efilive.com/

There's people there that are very good at Custom OS's.