wrangler engine dies

[brownduane]

I have a 89 yj with the 4.2 i-6 and automatic. The thing dies everytime I come to a stoplight. I have replaced the fuel filter, spark plugs, cap, rotor, and wires. I have searched for a vacuum leak and have found nothing. Could it be a worn out fuel pump? It starts fine, idles ok, and runs down the road with lots of power. The thing does however run rich at idle and when it is at speed and you push the throttle you can hear detonation. I am thinking either a bad fuel pump or maybe a bad ignition coil. The carbuerator appears to be a new one. I need a fresh perspective on this, it is terribly frustrating!

[Dan in KC]

Had same problem. short in starter coil. might also be the catalitic converter. Also have the MAP sensor checked.

[fliggyg]

I am having this same problem. I just bought a 1990 wrangler with 4.2L and it dies everytime I press clutch in and slow to stop. It also backfires a lot will coasting down hills when not pressing gas. Engine seems strong though..

I have little mechanic knowledge and want to learn.. it has aftermarket airfilter/breather.. I got the factory breather when bought it and was going to be put back on. i was going to try and check vacuum hoses (if can find diagram). What needs checked next?am i on right track?

I also noticed muffler rusted in half and it is load.. i figured that would help as well be replacin that...