Coil pack options?

pencilneck

Registered User
Well, my 89 SC is driving me nutty. The car runs great for about 10 minutes then starts cutting out/bucking and runs like crappola. I have put a replacement DIS module in with the heat sink goop but it does the same thing, supposedly it was from a car that ran "good". Now I've read here that I should put a new coil pack in there as they can take out the DIS modules. Screamin Demon makes a coil pack that looks to be universal for Ford 6's. I see one for 88 bucks on Ebay. Where will my cheapest source be for a good coil pack? I have yet another DIS unit on the way. Anything else to check that causes the car to run bad only when warm? The tachometer gets funky then and the engine doesn't want to crank over fast as it usually does when it is "acting up". Is there something else I should check, such as grounds, MAF sensor cleaning, etc?? I am beginning to dislike this car because of this symptom. Thanks, Roy
 
I just had the exact same issues with my 90 and the Screamin Demon coil pack I bought from that ebay seller was the cure. However, first I swapped in a stock coil pack borrowed from a friend to be sure that the coil pack was really the cause. I'd already replaced wires, swapped DIS modules, and the problem persisted. Sometimes the cam position sensor can cause similiar problems. I think ebay is the cheapest source for that coil pack...
 
A flaky crank sensor can also cause issues with the DIS as well. Its very rare our coil packs actually cause issues and are a very stout peace. I'd be more concerned that it would cover up an underlying issues that may in the end rear up and bite you.

As far as the heat goop goes. Make sure it is the heat sink compound and not dielectric grease. Also it only takes a very thin layer of the stuff. If its squishing out the sides of the DIS you've put to much on. Get everything very clean before mounting.
 
Oh, I forgot to mention that previous to all of this the car used to run great for long periods of time. Then one day the alternator failed to regulate. One very expensive new alternator later, and the problem began. Maybe electrical excess burnt out something in the coil pack? What I have not done is to pull apart the wiring in between all of the ignition pieces. It could be that there is a faulty wire in there somewhere. Is that a common problem? The other thing I am thinking is that maybe my battery has some sort of internal defect and that after a few minutes of driving the battery gets hot and the short/loose plate/whatever starts to show... Boy this is tough... I really need a new battery anyway so will get one today. I long for a MSD solution to this supercoupe problem. Why don't they manufacture a system for the car, surely they could sell alot of them, since the Mustang also shares the system???
 
Good luck with a Screamin' Demon coil pack if that's the route you choose :rolleyes:

I recently had the car running on like 4 cylinders, so I bought NEW: cam sensor, cranks sensor, DIS, and Screamin Demon.

The screamin demon was faulty and wouldn't fire cyl 6. Those who were at the shootout might have seen me swapping the coil pack for a 2nd screamin' demon coil pack at saturdays dyno day and show. I fired the car up, same problem, no spark on number 6. Many people saw it. I put the stock coil pack back on and she runs fine.

The Screamin' Demon coil packs are either hit or miss. I'm not the first person to have problems with them. I've had 2 bad ones in a row. I've only heard of a few that work properly. I suppose it would be nice to have a stronger spark, but the fastest cars in the club have stock coil packs so.... are they really that bad to begin with?

If you buy it from EBAY make sure you can return it to the seller if it's faulty. Apparently Performance Distributors doesn't test each unit they send out.

I finally said the heck with it after two different ones, and used the money I spent on that to put towards a bigger fuel pump.

Hopefully it works for you.

I tried to put a used DIS on my car but it wasn't any better. I've actually got the Auto Zone DIS modules on two of my SC's and they work great, lifetime warranty too. Cost like $100.00 and if the DIS is bad it doesn't matter what coil pack you have because the DIS controls when the coil pack starts to run through the firing order.

Even if the cam sensor goes bad the car will eventually get it right and run. Usually you lose tach signal, and the car will not start right up on the first try. It has to guess the correct firing order. Eventually (after 2-4 tries of key off and then restart) it will guess correct and the car will run.

When crank sensor goes bad, the car just shuts off and will not start for like 20 minutes.
 
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Oh, I forgot to mention that previous to all of this the car used to run great for long periods of time. Then one day the alternator failed to regulate. One very expensive new alternator later, and the problem began. Maybe electrical excess burnt out something in the coil pack? What I have not done is to pull apart the wiring in between all of the ignition pieces. It could be that there is a faulty wire in there somewhere. Is that a common problem? The other thing I am thinking is that maybe my battery has some sort of internal defect and that after a few minutes of driving the battery gets hot and the short/loose plate/whatever starts to show... Boy this is tough... I really need a new battery anyway so will get one today. I long for a MSD solution to this supercoupe problem. Why don't they manufacture a system for the car, surely they could sell alot of them, since the Mustang also shares the system???

Why can't you use an MSD box? DIS +4 or +6 and seperate coil packs. Bolt them all together, and they fire in pairs, you just program the firing order into the box. Then you get 2 stage rev limiters, spark advance and retard, etc..

Kevin Leitam runs an MSD ignition on his SC. He is the one that just ran in the 10's at the shootout. I'm sure there are pics of how he has it mounted and he could tell you how it's wired up. He is very open about his car and will share how he has done it. Great guy!
 
Thanks alot Scott, that sounds like pretty good advice. I'll just start looking for a replacement for everything, I didn't know Autozone had those DIS units. I run MSD in my 460 truck engine and I just love it. These cars are so awfully expensive. Thanks, Roy
 
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