Cold Idle Surge!!
nates6969
06-18-2005, 02:57 PM
Hey have been looking around the forums for the last while and it seems like everyone gets idle surge as soon as the engine warms up. I just finished throwing a 5 speed in my 91 talon N/T and its always had Idle surge but now its horrible with a 5 speed.
The problem: When I start the car it starts up fine reving roughly 1400 which seems a little high but once I put it in gear it kicks down to about 900-1000 but if I push in the clutch right after I put it in gear it starts surging like crazy from 1200-1600 but then if I go drive after about 3 minutes of regular driving and the car warms up, the idle surge is gone and the car idles perfect around 800. So ya...<b>it only does it when its cold</b>
So far I've checked and attempted to adjust the BISS which helped tune down the idle but did nothing for idle surge, put a new o ring on it, I also popped out the iac (the lower one right?) to check its movement when cycling the key on and off and the damn thing didnt move at all? how exactly do I test the thing, I've tried manually adjust the plunger in and out and that did nothing. I saw something about blocking off the FIAV but I live in a cold winter climate and is that a good idea? If you have any other tips please let me know.
The problem: When I start the car it starts up fine reving roughly 1400 which seems a little high but once I put it in gear it kicks down to about 900-1000 but if I push in the clutch right after I put it in gear it starts surging like crazy from 1200-1600 but then if I go drive after about 3 minutes of regular driving and the car warms up, the idle surge is gone and the car idles perfect around 800. So ya...<b>it only does it when its cold</b>
So far I've checked and attempted to adjust the BISS which helped tune down the idle but did nothing for idle surge, put a new o ring on it, I also popped out the iac (the lower one right?) to check its movement when cycling the key on and off and the damn thing didnt move at all? how exactly do I test the thing, I've tried manually adjust the plunger in and out and that did nothing. I saw something about blocking off the FIAV but I live in a cold winter climate and is that a good idea? If you have any other tips please let me know.
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