Have a 1989 IROC Z I have had since new (October 1988). It sat for several years but recently (3 years ago) had new lines, fuel cell, etc., put in and it has run fine. In the last few months, it will start and run (sometimes without issue) and other times it will completely shut off (while driving) and then will just turn over when I try to start it. Other times will just not start period. It recently did it to me at work and when I came back the next day it started fine and had no issue for several runs. Yesterday it started, pulled out of the drive and then started cutting off for short (.25 sec bursts) before stopping completely. It cranked and started long enough for me to put it back in gear and get it up the drive. After sitting overnight, it started immediately, pulled out of the garage, drove 50 feet and it shut off again. Not sure what the issue might be. Thoughts?

 

Have you check basics yet ? Spark, fuel pressure and even ohm injectors ?

 

Sounds like either the rotor or the ICM.

As Tuned said, do the basic checks; concentrate on spark first. Obviously you want to do your checking while it's in the act of screwing up.

 

Yep. No spark. Getting fuel.

I will try to replace the ICM and see what that does ...

Thanks for the thoughts.

 

Start with the rotor.

 

Changed the ICM (and the rotor while I was in the area) last Wednesday night after work. Old ICM was factory original and looked pretty rough. New one seems to have solved the problem. We'll drive it around close by for a bit to be sure tho!

Thanks everyone for the input!

Doug

J. Douglas Boles
@jdouglas4

 

Here is a video my team posted of the ICM change out ... from IMS Twitter and IMS YouTube.

https://x.com/IMS/status/1702661039567859997?s=20

You Tube