Crank no start

[Kmcdivitt]

Just bought a 94 yj the other day. Drove it 2 hours everything was great. Did a tune up and oil change on it then it wouldn’t start. It will sit there and crank but refuses to fire up. I double checked the firing order and put all the old stuff back on just in case but no luck.. what would cause it to be doing this out of the blue?? I’m lost

 

[jpjeep26uk]

Hi, I would start with your ECU. I just spent nearly three loooooooooong months with the same issue and replaced 10 items in the engine bay to try to figure out the busted bit. It was a fried ECU all along. I'm not saying thats your problem area, but it might save you a tonne of time starting there instead of doing what I did and wasting time, money and in my case hair!