warm idle surge, no cel? HELP!

[P.I.M.P.]

Ok, i read thru tons of idle threads in the archives and i only found one w/ warm and it was a cali car w/ an egr valve, so it dosent apply. So heres the dilly:
When it was cold outside i had a small idle surge at warm start up and once driven it was gone. That i could live with. Well now its 70 here and the idle surge goes from 1500 down to 1100 and back up and down and up and down etc. Hot starts the rpms start at 2100, drop to 1500, fall to 1100 then back up to 1500, etc. Last night i had to give the car gas at start b/c it wouldnt hold an idle at first, it just kept falling on its face and shutting off. Its like the ecu wants to drop the idle down to 700 but something just wont let it. A side note, i do have a small crack in my exhaust mani. I checked for vacum leaks and i have none. Im going to take apart the TB and clean everything but is there anythin imparticular i should pay attention to. Is the change in temp and the idle problem just a coincidence or does it point to a certain part? Thanks for any help.

 

[92 AWD ECLIPSE]

Mine is doing the same thing, sometimes when I start the car it will stall, and shutter. The other day it was idling at 1600, very annoying. Any help would be appreciatied.

B

 

[CurtTSI]

I had a similar problem. Turned out to be a bad coil in the ISC. In my case, the ISC worked OK at start up, but when warmed up, would idle surge and finally just die at idle. Resistance tests on ISC coils showed good when cold, but when the ISC got hot, one coil went open circut. First thing that I would do is to test the ISC coils after warm up. You can do this with the ISC still on the car. Resistances between the 2 center pins and the two pins on each side of them should be between about 28 and 32 ohms.

 

[P.I.M.P.]

Thanks for the help. I dunno where the isc is, i checked the overview and it just says it isnt seen here. i know its not the one on either side, tps and idle switch, so is it the one underneath? Thanks.

 

[crankbender]

check this out guys.

http://www.dsm.org/how-tos/tttt/tttt3.html

 

[CurtTSI]

Yes, it's on the lower left side of the throttle body. There is a 6 pin connector attached to it.

 

[P.I.M.P.]

you guys r great, thanks.