ICM was my problem, took it down to Napa and they confirmed it. 
No spark question
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,079
Likes: 816
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
No spark question
So, my car cranks but won't start up. Went to see if it would fire up earlier. It didn't, engine temp was at 157 via the digital readout. My dad hooked up a spark tester to a plug wire and the coil. No spark from either. Do you guys/gals think it's the opti?
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
... The easy way would be to start at the Ignition control module and coil ... have the module tested and hot wire the coil ... they're both easy enough to get at ... then start your search for an Opti spark distributor .......
Le Mans Master
Joined: Sep 2009
Posts: 6,320
Likes: 1,131
From: Vermilion OH
ok, first thing to check in my opinion would be to test spark from the coil. if you have no spark from the coil to the opti spark then you may have a faulty coil or ignition control module. you can have the ICM tested but not the coil. if you have spark from the coil, check for spark at one or more of the plug wires. if you have spark then its time to start looking elsewhere. if you do not, then it may be a faulty optispark distributor.
i recently ran into the same issue. car sat all winter and then would not start. after testing multitudes of things, i had the ICM tested. it tested bad, so i replaced it and i have had no further starting issues. i did have to replace the optispark distributor and the coil last fall.
i recently ran into the same issue. car sat all winter and then would not start. after testing multitudes of things, i had the ICM tested. it tested bad, so i replaced it and i have had no further starting issues. i did have to replace the optispark distributor and the coil last fall.
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
Another thing to check is the connector at the opti for the wire harness. Over time things may get doen into that connector and cause the female connectors to corrode. But be very carefull trying to get the plug out, it will most likely be rather brittle and want to break. I say check this because mine had at some point some coolant leak down inside and ate away at the connections. Put a new harness in and you'd a thought it was a brand new opti.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,079
Likes: 816
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
I replaced the ICM about a month ago, applied the heat protection. Lt4obsesses, I cleaned my opti connection last week, and the car ran noticeably better. I'll get my ICM tested out.
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