the car has been running funny lately but it had not been throwing any codes at all. Today, it threw a code 42 (IST Grounded) but this may have just been a fluke as it did it when the car was cranking.

Car usually starts then immediately dies. You try to start and it does this a few times. If you give it a little gas, it will start and miss badly. If you leave it running, about half the time, the car will smooth out. Once you have the car started and it's running, it runs fine the whole time for that run cycle.

Any ideas??

 

Is your fuel pressure ok? Fuel filter?

 

Pressure seems fine. Brand new Walbro 255 pump and a newer filter...

 

had the same problem three days ago the icm was going out
good luck

 

Well, if it is the icm, that's easy enough to get tested. Autozone.

 

I have already tried a different ICM and had a new coil laying around and plugged it in. Neither fixed the problem. I have good fuel, good coil, good ICM, good PCM. Only other thing I can think of is the opti is coming apart inside or just going out. Is this feasible?

Ryan

 

go to shoeboxes web site and you can find out how to test the opti

 

That tells how to test the optical portion, not the cap and rotor section. I am thinking that the cap and rotor is trashed at this point.

Ryan