Could you have a problem with the distributer itself causing the coils to go? What is the condition of the plastic at the coil plugs? I have over 420K on my car and the coil died once and I had to replace the distributer once but I never smoked a coil. The coil died suddenly and I could not start. The distributer would cut out intermittently and the engine may or may not start again. I put in a remanufactored distributer from NAPA and I have not had any trouble since. (The two problems I had were not at the same time either.)

 

The dist. Is brand new.

 

are all the coils you put in the truck the same brand? did you get them all from the same parts store?

 

No different brands and different stores

 

i would try msd then.

 

Ok so I replaced the coil because the other coil looked like it blew the guts out the bottom of it. I went to the truck and it fired right up. Luckily I got it home, and then it died in the driveway. I am assuming that the ignition module is going out. The ignition module came with the new distributor. Could the ignition module fry coils? I am so frustrated with this damn truck. I am almost ready to roll it off a cliff.

 

I do not know enough about the ingition module internal wiring but there is a lot of current flow through the Ignition module that it very well could be a defective ignition module. A coil is pretty simple device and your distributer is funtioning there is something occurring out of the ordinary to fry your coils. I would get a junk yard ignition module and coil for low cost and give it a go.

 

I found this doing a search. It is for a jeep but the circuit could very well be the same.

Scott, I suspect that your ignition coil is meant to normally run off a reduced voltage through either a ballast resistor or a resistor wire and it has been somehow connected so it's seeing the full battery voltage instead. Further, it is likely only supposed to see the full 12 volts only while you're starting the engine. A standard ignition coil meant for a vehicle that works like I'll describe below could overheat and fail if wired so it gets the full 12 volts all the time.

What happens is, if your Wrangler is a year that works this way anyway, the coil is supposed to only be connected directly to the full 12 volts when the ignition key is in the Start position, to give a bit hotter spark to help the engine start more quickly. Then when you release the ignition key to the Run position, it then gets a reduced voltage through either a ballast resistor or (more likely) a resistor wire. It's designed to run normally on a reduced voltage and only briefly on the full 12 volts only while the engine is being started.

At least that's how it is on older Jeeps, your '93 is in a gray area for me so far as whether or not it operates that way. But seeing as your YJ is burning up ignition coils, it's seeming like yours may work that way too.

Finally, an ignition key switch has two +12v connectors that end up at the ignition coil, the Start and Run connectors. The Start connector goes directly to the ignition coil. The Run connector goes to the resistor wire or ballast resistor which then connects to the same ignition coil connector. The + side of the coil has two wires leading to it, one from the Start connector and the other from the Ballast Resistor. Pretty simple and ingenious how they came up with that.

 

I had a chance to look at the factory electrical diag. and trouble shooting procedures. The checks consist of using an Ohm Meter and checking resistance at the coil and at the distributer pick up. The Haynes manual has the resistance checks at both the distributer and at the coil. The tachometer pick up at the coil must not be grounded. There are only two things connected to the coil the distributer and the Ingition Module. So one these items is faulty. I would do the resistance checks before throwing any more parts at it. After looking at the diagrams and I would suspect the distributer over the ignition module. The Ignition module applies 12V in run and start.

 

Thanks alot for all your help I am going to try to take a look at the truck tomorrow. I haven't had much time lately. Also, if I can find out which wire is which. Blah.