So about a month back my truck started giving me problems where id be driving and it would randomly start backfiring and runing very poorly. I took it to a shop they told me it was a bad coil which was replaced and the truck seemed to be fine for a couple weeks and now im having similar problems. Sometimes it wont start so i spray wd40 on the coil and i t fires right up idk what the problem is but if anyone has advice id appreciate it thanks guys.

 

Check the primary wire connector at the bottom of the coil. I'm assuming you have a Magnum V8. For some reason my connector stopped "snapping" into place and I've got several tie-wraps on it holding it in place. If it's not that, then I would be looking in the direction of the crank sensor.

 

Maybe the coil is defective, what brand is it? Or maybe the wire is bad or not pushed in all the way.