I just, changed my coil, plugs, and wires to fix an arking issue. The car ran great for a couple of days but now while i'm driving it runs great but when i come to a stop the cars idle bounces back and fourth from 700 to 500 and sometimes a lil lower, but when i take off it's perfectly fine. Seems to only do it after it warms up usually ...If i sit still long enough it will quit and idle at 700

 

are you throwing an SES light???

 

No, I have no ses light on. Nor did it come on when my coil was arking, and it was running on 7 cylinders because the #7 wire was blown in half. I'm not sure how the light wouldn't come on... I have a code puller in my car and a couple months ago i plugged it in and it flashed the no code so i'm sure it all works. Maybe i should check again?

 

I remeber reading your coil thread and i'm telling you i had all the exact symptoms as you. Almost dying at stop sign but only after it was warm and such. I ended up changing the ICM and the opti and it fixed the prob. Couldn't tell you which one was causing the prob because i changed them at the same time. But i would guess it was my opti.

 

Ok, I scanned the car anyways, it flashed 12, 28, 61, 71... I know 12 is no code but in my book the codes are for multiple vehicles so im not sure which specific one it is for my car.

28- 3rd gear switch or quad driver module (which says corvette) or transmission fluid pressure switch assembly open or short circuit porblems

61-O2 sensor degraded or port hrottle system error or cruise control problems-vent solenoid circuit. Or a\c system performane problems.
Now this one is hard because i just bought the car, the ac isnt blowin cold, the cars havin bad gas mileage and the cruise cntrol recently quit lol so got all of those problems

71- ac evaporator temperature sensor-signal voltage low

 

Shoebox has an LT1 specific code list, including the 93. Open the list, and look over to the right hand side for the 93 codes, where they are different than the 94/95.

http://shbox.com/1/Dtcs.htm

DTC 28 is the fan relays and A/C relay.
DTC 61 is AC system performance
DTC 71 is AC Evap temp sensor

That wouldn't appear to be related to the problem with erratic idle.

There was no code for the misfire, because there are no codes for the high voltage side of the ignition, or for misfires in OBD-I. The suggestion about the ICM is a good one, because they can get heat soaked. See Shoebox's fix for moving the ICM away from the head.

The idle problems could also be related to problems with the IAC motor or a dirty IAC passage.

 

Alright thanks for the help, i found an ohm test for the IAC on shoe box i'll check that and if it is okay i'll swap the ICM i suppose... fast easy fix