Inconsistent Spark
 

I have an '89 jeep cherokee that is haveing some issues. When I bought it the old owner said that it would start but had no power due to a blown head gasket. Well I replaced the head gasket and it still has the same issue. So after a little more investigation I found that the jeep does not always spark. It will start and you can rev it up but then it will start to die, and you have to keep pllaying with it to stay running, then it will rev up again, however the whole time it does not have to power to move itself.

We hooked a timing light up to it and we found that sometimes the light would blink just like it's supposed too, but then it would start to blink eradically, or just not blink for a second or two, I'm guessing that this is happening on all the cylinders(but we only checked the #1) and that is what is killing the power. However I am not really sure where to start looking for the problem. Any help would really be appreciated. Thanks Alot guys

have you checked your cap and rotor? cracks, wear. burnup.

The cap and rotor look good, a little dirty but overall they seem fine

when was the last tuneup?

i'd say start with the basics: clean the cap and rotor if they still seem good (or replace, which never hurts), replace the plugs, wires, and check the coil. if these don't fix the problem, then you may have a control unit to replace.

Alright, thatnks alot guys. That helps alot