94 wont start
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
94 wont start
For the past 2 weeks it would start fine but was running a little rough for about 30 seconds and then ran great. Drove it to my girlfriends house and parked it Saturday night. We used her car on Sunday and when I got in it that evening, it turns over, I can smell fuel, but it seems like there is no spark. Can a coil or ICM go out just like that ? I was told the opti is newer and it has an electric water pump with no leaks and it has not gotten wet either. Is there an easy way to check the coil and ICM ?
Thanks
Thanks
Burning Brakes
Joined: Aug 2010
Posts: 833
Likes: 1
You can take the ICM to a local auto parts dealer like auto zone and they will test the ICM for free. Be sure of what's causing the problem first. Make sure you have no spark, and if you do, check the fuel pressure.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
Did the noid test and that was fine. Does that rule out the opti ? No getting an arc out of the coil when cranking the engine and I am getting a pulse and voltage at the icm.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
That basically rules out the opti because the low resolution pulse is the main clocking pulse for the PCM and if you are getting injector drive that means the optical portion of the opti is working. The cap of the opti can be forgotten about at this point, not a factor.
I would measure the drive for the ICM from the PCM. Remove the ICM connector and measure pin "B" for 1.0 to 4.0 VAC while cranking the engine. If you have the drive voltage the problem is probably either the ICM or coil. The ICM has a larger probability of going bad. As said the ICM can fail with no warning, it is a solid state amplifier.
At that point I would either get it tested (if you can) or just replace it (best way).
If you did not have the drive to the ICM then you would have to look back at the PCM for the problem but I don’t think that is going to be the case. Also make sure there is 12 volts on terminal A and D of the ICM connector which comes from fuse #25, 10A.
I would measure the drive for the ICM from the PCM. Remove the ICM connector and measure pin "B" for 1.0 to 4.0 VAC while cranking the engine. If you have the drive voltage the problem is probably either the ICM or coil. The ICM has a larger probability of going bad. As said the ICM can fail with no warning, it is a solid state amplifier.
At that point I would either get it tested (if you can) or just replace it (best way).
If you did not have the drive to the ICM then you would have to look back at the PCM for the problem but I don’t think that is going to be the case. Also make sure there is 12 volts on terminal A and D of the ICM connector which comes from fuse #25, 10A.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
It was the ICM I also replaced the coil for an extra $20. Runs and starts better and my fans did not kick on right away like they used to. That seems odd but I dont care, its running again.
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Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,846
Likes: 129
From: Orlando Florida
