Engine Going through ignition coils

[Xkuzme1]

Hey guys, I’m scratching my head on this one.

93 mustang, mostly stock ignition, MSD cap and rotor, but stock everything else. I have went through 2 Ignition coils in the last two days. Car was running but would intermittently quit. I changed the coil and started better and ran perfectly. I was letting it idle in the driveway and it quit again. Just quit. Hooked a spark tester up and there is no spark from the coil.

If anyone has any thoughts on this one, I’d love to hear it.

Thanks,

x

 

[General karthief]

This should help you out.

Cranks OK, but No Start Checklist for Fuel Injected Mustangs

Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995 A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work...

www.stangnet.com

 

[Wayne Waldrep]

Went thru the same thing except mine lasted over two years. Finally figured out the junk coils were just that...junk. I got a better one apparently now because no problems. The terminals on top would separate internally and lose contact....no spark. You couldn't tell outside until it would finally come apart. The new one has a brass terminal. When I put it on it instantly stopped all the crap. That's been months now and still fine. Mine is just the best one I could get at O'Reilly.

 

[Xkuzme1]

I bought a new one from Napa. I bought the expensive one. It worked for a few mins. I took it back and they only had the cheap one. I bought it and installed it... seems to be doing fine.

I did add a grounding strap to one of the mounting screws. (My install isn’t in a mustang, it’s in an AC cobra, but all parts are donor from an 1993 mustang). Wondering if I wasn’t getting a good ground.

 

[Xkuzme1]

Running Good now.

Running

 

[General karthief]

Hey guys, I’m scratching my head on this one.

93 mustang, mostly stock ignition, MSD cap and rotor, but stock everything else. I have went through 2 Ignition coils in the last two days. Car was running but would intermittently quit. I changed the coil and started better and ran perfectly. I was letting it idle in the driveway and it quit again. Just quit. Hooked a spark tester up and there is no spark from the coil.

If anyone has any thoughts on this one, I’d love to hear it.

Thanks,

x

this is a little different than a cobra kit car!
That was a little misleading, the advice may have been different if this was revealed in the beginning.

 

[Mustang5L5]

A lot of parts being made these days for the 80's and 90's Mustangs are junk, especially electronics. Even motorcraft parts have been sourced to different vendors than what was used 20-30 years ago and the quality isn't there.

I replaced my coil with a good, used OEM coil. I have more faith in that, than recent built units.

 

[MustangIIMatt]

A lot of parts being made these days for the 80's and 90's Mustangs are junk, especially electronics. Even motorcraft parts have been sourced to different vendors than what was used 20-30 years ago and the quality isn't there.

I replaced my coil with a good, used OEM coil. I have more faith in that, than recent built units.

It seems to move forward as time marches on, Duraspark modules and external voltage regulators for the old Ford alternators were virtually impossible to find a good source for 15-20 years ago, but you could get good electronics for 80s and newer Fords all day. Now you can add them to the list, and even the stuff from 10-15 years ago is getting hard to find quality parts for.

 

[Mustang5L5]

It seems to move forward as time marches on, Duraspark modules and external voltage regulators for the old Ford alternators were virtually impossible to find a good source for 15-20 years ago, but you could get good electronics for 80s and newer Fords all day. Now you can add them to the list, and even the stuff from 10-15 years ago is getting hard to find quality parts for.

Yup. Time to stockpile that stuff.

I would imagine that attrition is the main culprit. Ford had 302's in just about everything back in the 80's and 90s. Now, how many are actually left on the road? As the numbers drop, it's just not cost effective to keep making these parts, so they go with cheaper and cheaper vendors based on lower quantity pricing breaks.

I remember back in the 2000's if you hoped on Rockauto and pulled up any misc sensor on the 5.0, you would see maybe a dozen vendors for that sensor. Now there are only a handful. If you pull up a sensor on a newer car, you'll likely see a lot of choices. Old cars are just...old. Not a lot of demand, therefore not a lot of competition and as a result, quality suffers.

 

[91GTstroked]

Anyone try the screaming demon coils?

 

[jrichker]

It seems to move forward as time marches on, Duraspark modules and external voltage regulators for the old Ford alternators were virtually impossible to find a good source for 15-20 years ago, but you could get good electronics for 80s and newer Fords all day. Now you can add them to the list, and even the stuff from 10-15 years ago is getting hard to find quality parts for.

Now I don't feel bad about all the old parts that I have been saving...

 

[Xkuzme1]

So a follow up.

It seems that one of the wires going into my coil had a short in it. It was a broken wire that when it got warm expanded enough to make a connection. For some reason, which I don’t understand, this situation caused the coils to fail. Honestly, as discussed, the coils are made pretty damn cheap these days.

I used a spark detector connected between the coil wire and the distributor. I had my son keep turning over the car while I moved and pinched the wires until I found the exact smoking gun. There had been a hard fold in the wire.

Now that it is all figured out... presumably the MSD coil is the best option and best made, I just ordered one of those. Seems that the Motorcraft used to be the best but they have stopped making them.

I hope this helps someone else. This forum has been so helpful with ironing out the kinks to my car. I’ve got 1900 miles on it now. I can’t wait until spring to drive my car.

X

 

[Xkuzme1]

Update:
I’ve been driving around my car with no SPOUT chip in for a couple weeks. It’s starts great and runs great. No issues other than obvious destination because of the lack of timing advance. So I’m posting in several different threads with an update. Turns out my problem was not the coil.

I ordered an A9L computer from NAPA. I took my computer out and swapped it. With the spout chip back in, it started right up. I rolled it out in the driveway to let the new computer adjust to the timing and idle air setting. I didn’t have time to drive it yesterday, but I assume that all will be good.

Thanks for all of y’all’s help.

x