Car ran fine two weeks ago, now won't idle, wants to die when in gear and won't hold revs while in neutral with throttle partly engaged. Example - idling roughly around 500, give it gas to keep it alive and I hold it at 2K. The idle will just fall flat down 500-1500 revs fast like i turned it off, all while keeping my foot in the throttle, then it will finally wake up and pop up to 2K. It will do this over and over. This car is new to me, I don't have all the mod history. Here's what I've done so far - replace plugs, Clean TB and IAC, found and removed an ADS Super Chip from 1997, performed base idle reset procedure, check TPS voltage (got .97v). It idled fine once right after removing the chip, then back to crap at next start. Any ideas?
Mods - Edelbrock Performer heads and intake, unknown spec Comp cam, BBK 70mm EGR, stock TB (no idea why that's still stock), FMS big bore 70mm MAF for 30's, 30# injectors (I know, too big, car had a blower that died and was removed), Lentech AOD, off road X, Bassani catback.
Mods - Edelbrock Performer heads and intake, unknown spec Comp cam, BBK 70mm EGR, stock TB (no idea why that's still stock), FMS big bore 70mm MAF for 30's, 30# injectors (I know, too big, car had a blower that died and was removed), Lentech AOD, off road X, Bassani catback.