1994rcsbLS
Newbie
doing this in morning. And checking vac as well. Also. Running a rear setup with no parking brake.Hmm,
Good test for that would be block booster,run engine up to about 3000 in park and hold it there a few seconds and chop the throttle and see if it drops down below your set curb idle or stalls all together. If all goes good with that then set the parking brake HARD and using the foot brake do a stall test and see if it falters. If it passes that test it's pretty much a given the booster is shot.
Will check in morning. Also it was tuned by a reputable shop in nc so I’m sure whatever needed to be done was done. Converter I don’t think has a play here as this is a newish issue.My best guess is the converter is too tight and possibly have a leaking booster and thus it leans out. What is your idle vacuum in gear? 6 in/hg? Are you using idle spark timing variation to help control the idle speed?