2000 GT, Slight delayed surge at idle, exists under regular load but extremely pronounced with A/C on... Car starts out idling around 900rpm and slowly the rpm's decrease until around 600rpm when they plummet to around 300-400rpm where the engine feels like it will stall and then it revs itself back up to 1100rpm and the cycle repeats.
I can also replicate this same scenario by depressing the brakes fully at idle or rolling up both windows simultaneously. Putting the car into gear sometimes has the same affect.
I've already cleaned the IAC but to no avail. Car has done this for probably the last 2 years, only driven in summer sits in a garage for ~7months a year. Runs extremely well otherwise...
In terms of mods, K&N, O/R prochamber, rebuilt and strengthened 4r70w custom dynomax catback, and Bama race tune (just recently installed so its not the tune)...
I can also replicate this same scenario by depressing the brakes fully at idle or rolling up both windows simultaneously. Putting the car into gear sometimes has the same affect.
I've already cleaned the IAC but to no avail. Car has done this for probably the last 2 years, only driven in summer sits in a garage for ~7months a year. Runs extremely well otherwise...
In terms of mods, K&N, O/R prochamber, rebuilt and strengthened 4r70w custom dynomax catback, and Bama race tune (just recently installed so its not the tune)...