my center ignition coil went bad, replaced that one only. Drove it around for about half an hour...on the way home a couple of blocks away from my house it started going bad again. I stopped, and turned off the car...tried starting it again...had a hell of a time trying, but when it DID start...ran like sh** and wouldn't move, basically no more spark.

Basically what i want to know is...what could be causing my coil to go bad? is it a short somewhere? bad fuse? incorrect size fuse? what is it?? i can't figure it out. I don't want to keep replacing coils, because thats expensive. any help please?

 

How sure are you that the old coil was bad? Did it fail the resistance tests, or just didn't seem to put out a spark?

I'm wondering if you have an intermittent bad connection on the harness, and maybe just swapping out the coils moved it around enough to make connection for a while. The new harness is about $57 at Mazdaformance, and it's probably worth changing if you have to go in there, assuming you haven't already changed it.

Good luck,