My question is on a 98 pcm for a 5.7l vortec,is it possible that the shop that programmed this computer using Ls1 edit could have deleated the ability for the pcm to compensate for a/c request.This computer does not adjust IAC counts at idle or cruise and it is causing the truck to buck slightly when ever the compressor cycles.I am told by mitchell on demand that it should change injector pulse width to smooth the cycling of the compressor but could not get that info from my scanner to verify that it does not but by the way it draws the motor down i would say it is not changing this either.The shop that did the programming tells me they did nothing to program this out but i am skeptical to say the least.They also built the wiring harness for this application and did not wire it the same as the factory,so i dont know which way to go with it to fix it.....Input would be very appreciated!!:

 

There is a table in LS1EDIT to adjust idle speed with the A/C is engaged and well as conditions where the clutch is disengaged.

 

It is not the rpm at which it idles it is the fact that the computer is supposed to compensate for a/c compressor cycling and it does not do it.Is it possible they took this function out or does LS1 edit not allow for you to delete this function.I am leaning toward the fact that they wired the harness wrong but it would sure help to know if they could take this out of the pcm function. Thanks for the input!!

 

I don't recally seeing any table for the A/C compressor other than idle speed and clutch disengagement at higher RPM.

When you engage the A/C the computer compensates for the lost idle speed. If that is not what is happening, I have no idea.

 

Thanks for the help I am going to wire this a/c system back to the factory spec's before I get to far into the computer and see what it does. I appreciate the response!!