1G Intermittent spark, no start problem

[Rex2342]

Wednesday on the way home from work my car died. It simply shut off and would crank but not fire. A quick look on the side of the road determined I was getting fuel but I didn't look much further. After sitting a few minutes it fired back up and all was well again until yesterday. I drove to work without a problem but went to get lunch and it died again. This time it would fire up for a short time and die again. I was able to determine this time around that I had no spark and I was getting no rpm signal on the factory tach while cranking. I swapped out the CAS on the side of the road and it still would only run for a short time. I ended up flat bedding it back to the shop so I could look it over better. Once I got it back to the shop I swapped the CAS back. It was running better and for longer periods of time. It idled for a bout 20 minutes and I drove it around the shop until it died once again. I put an in-line spark tester on it and it's getting a weak spark occasionally while cranking.

At this point I'm thinking it's either the transistor or the coil. I don't have the 90 replacement parts readily available but I do have a 91-94 coil, CAS and transistor with pigtails sitting here. I've been wanting to swap these parts over for some time but I don't have the 91-94 ecu or the 91-94 cluster to correctly do the swap. Can I wire these parts in and still use the 90 ECU and cluster? I've read most of the articles in the forums and haven't found an answer to this. The CAS is easy enough but the transistor and coil are not so simple. I remember an article on the VFAQ that is since long gone that gave step by step instructions for the wiring connections. Does anyone have this article or able to help me out with this?

 

[psiaddict]

At this point I'm thinking it's either the transistor or the coil. I don't have the 90 replacement parts readily available but I do have a 91-94 coil, CAS and transistor with pigtails sitting here. I've been wanting to swap these parts over for some time but I don't have the 91-94 ecu or the 91-94 cluster to correctly do the swap. Can I wire these parts in and still use the 90 ECU and cluster? I've read most of the articles in the forums and haven't found an answer to this. The CAS is easy enough but the transistor and coil are not so simple. I remember an article on the VFAQ that is since long gone that gave step by step instructions for the wiring connections. Does anyone have this article or able to help me out with this?

I did not find your answer here but just in case you needed the VFQ Link:
Visual Frequently Answered Questions - Home Page

I did find this write up with a lot of info, unfortunately, I think it confirms what you thought and that it may not be possible:
http://www.dsmtuners.com/forums/art...4-ecu-swap-into-1990-dsm-ignition-wiring.html

look it over if you have not already, maybe it will help.... good luck!

 

[Rex2342]

I've read that article and that's probably what I'll end up doing if I can't figure out another way. The Vfaq used to have the article in question. The link has since gone dead but it was a how-to on swapping it all over complete with the later cluster and coil. I believe the original article was actually linked in it the thread you posted but that link is dead too . I've got both wiring diagrams for each year at the shop but I'm afraid I'm not very good at reading them. I'll grab them tomorrow and post each one and maybe we can figure it out before I start cutting wires. Then we can replace the missing article for anyone who needs it in the future.