Ignition Problems

[Woohoo123]

My having ignition problems on my 72. It won't turn over, and no spark from coil. I currently have msd 6al, along with msd blaster 2 coil, and mallory unilite distributor. I replaced the module in the unilite about a year ago. From what the guy at the shop told me was to get a new distributor, because the modules go out often. Anyway it ran for a while after I installed it, but within the last few months nothing. There is a youtube video on how to test the module. He says in the video, before testing the module, you have to test the coil. It should read 8-12v on the multi meter depending on how warm the resistor is. So, when test the coil is reads 1.54. When I disconnect the green wire from the neg side of the coil which leads to module, it reads 9.52. Hopefully someone has had the same issue. I'm trying to find out if the problem is the module again or maybe the msd 6al, or possibly something I may have over looked

 

[hyena429]

Coil mite be going bad...But i would try and run a hotwire from your battery positive side over too the coil ...hook it up too the side that says batt or positive....Then you know for sure that 12 volts are going into the coil atleast...and test again...These cars are full of fuseable links and such that can go bad over time and just give you a trickle of juice that is needed.....You cant get the starter to crank over either?...Sounds like some electric gremlins in your car....i hate them!! lol could even be a netrual safty switch..but really throwing darts with out being there...lol

 

[Woohoo123]

Thank you I will try that, and see what happens. The car does crank, but doesn't turn over. The coil is about a year old, not sure how long the life span is with those. I was thinking just rewiring the whole ignition, in case there is a short. But not sure yet, I don't want to do something that is unnecessary.

 

[73vertproject]

Thank you I will try that, and see what happens. The car does crank, but doesn't turn over. The coil is about a year old, not sure how long the life span is with those. I was thinking just rewiring the whole ignition, in case there is a short. But not sure yet, I don't want to do something that is unnecessary.

Welcome to the site. Someone should be along shortly with some info for you - wish I could help, but I haven't had coil problems yet.

If you get a chance, post a short intro in the Introductions thread so we can give you a proper welcome.

Doc

 

[Woohoo123]

Thank you I will try that, and see what happens. The car does crank, but doesn't turn over. The coil is about a year old, not sure how long the life span is with those. I was thinking just rewiring the whole ignition, in case there is a short. But not sure yet, I don't want to do something that is unnecessary.

Welcome to the site. Someone should be along shortly with some info for you - wish I could help, but I haven't had coil problems yet.

If you get a chance, post a short intro in the Introductions thread so we can give you a proper welcome.

Doc

Great! Thank you for the warm welcome

 

[Machman]

My having ignition problems on my 72. It won't turn over, and no spark from coil. I currently have msd 6al, along with msd blaster 2 coil, and mallory unilite distributor. I replaced the module in the unilite about a year ago. From what the guy at the shop told me was to get a new distributor, because the modules go out often. Anyway it ran for a while after I installed it, but within the last few months nothing. There is a youtube video on how to test the module. He says in the video, before testing the module, you have to test the coil. It should read 8-12v on the multi meter depending on how warm the resistor is. So, when test the coil is reads 1.54. When I disconnect the green wire from the neg side of the coil which leads to module, it reads 9.52. Hopefully someone has had the same issue. I'm trying to find out if the problem is the module again or maybe the msd 6al, or possibly something I may have over looked

Firstly ::welcome:: to the site,

I have the same set up in a different car and had similar problems in the past.

The module is usually hardy and my first one lasted over 10yrs,

Usual culprets in these types of systems is the coil, my car had a POS Acell coil which are known to fry or turn to garbage after a few months so check your coil first.

The mallory system is ment to be used with a ballast resistor (special mallory type) or it will also work ok if the car has resistance wire built into wiring harness

These 2 things can cause problems with the mallory system so check them out first before suspecting the module.

AJ

 

[will e]

I have used two uni-lite, the first one lasted forever and I would probably still be running it except it was a COMP 9000 and was too big to clear my induction set up. I liked it so much I replaced it with the smaller unilite.

Stock our mustangs used a resistor wire to the coil. The actual voltage when the car was running was something like 2 or 3 volts. it has something to do with the lower voltage being able to feed the coil at higher rpms faster than the full 12 volts (or maybe it was to keep it from overheating). Anyways...

On the starter solinoid there are two small terminals. One is marked S and one I. The 'I' terminal is 'Ignition' and what it does is provide 12v to the coil during cranking. Once the engine starts (and you no longer have the solinoid enguaged) the coil goes back to the resisted value.

But you have modified a lot.

I can't answer your question. I can tell you I have the unilite and a mallory coil. I ran it for a long time with the ballast but finally figured out I didn't need the ballast because I had kept the resistor wire.

I am not sure what I did with the 12v from the "I" on the solinoid. I need to go check that out.

 

[Machman]

Here is a link for wiring , troubleshooting and testing the mallory ignition

http://prestoliteperformance.com/Portals/0/downloads/mallory/pdf/Mallory_Instructions_unilite_distributor_wiring_diagram_test_procedure_1214M_0000.pdf

 

[hyena429]

Thank you I will try that, and see what happens. The car does crank, but doesn't turn over. The coil is about a year old, not sure how long the life span is with those. I was thinking just rewiring the whole ignition, in case there is a short. But not sure yet, I don't want to do something that is unnecessary.

I just ran into this issue with a little mustang ii i pulled out from under a tree its been sitting for 15 years....It would turn over but no spark...i ran a wire over to the coil from the bat...just to eliminate the ignition from my trouble shooting....and the sucker fired right up...You can see on the video below my wire runing from the clamp too the coil keeping the car alive...Figured out nothing was wrong..besides in my fusebox....And atleast you know 12 volts are making it too the coil...Counts where its going after that..lol

 

[will e]

Keep in mind the 12 volts to the positive on the coil direct from the battery is for trouble shooting only. You don't want to leave it this way.

 

[hyena429]

Keep in mind the 12 volts to the positive on the coil direct from the battery is for trouble shooting only. You don't want to leave it this way.

{thumbs up}By no means is this a perm fix.