I have a 90 YJ, carb'd 258. I bought it about a week ago and when you fire it up, as soon as it got to operating temp, it died. Wait a minute, and it would fire right back up and be fine. The PO had cobbled up the fuel system, so I had a new pump put in, we took out the tank its been cleaned and clean fuel back in. That did not solve it. From a cold start, when it gets up to operating temps, it dies. Sit for a minute, and fire it off and it wll go again and not die. I have read that this seems to be a common issue but suggestions have ranged on other threads from CPS, to nutter bypass, to ICM. Anyone have the problem and fixed it?
05-18-2013 03:45 PM
I'm new to the jeep world and the forum, but I am having a very similar problem. As soon as mine warms up, it will not idle and doesn't run very well under throttle either. It dies at every stop sign. It's got a new fuel pump, filter, pressure regulator, Weber 32/36 carb, and ignition coil. Runs great cold, but not well warm.
05-18-2013 05:49 PM
Your carb might need a rebuild or replacement. Make sure you change the fuel filter. You can first try and clean the carb. Carb and choke cleaner works. And, your idle hot and in park/neutral should be at least 750-800 rpm.
05-19-2013 09:32 AM
usually build up in the carb, pull the top cover and take a look, very easy to do,also check the intake manifold for leaks
05-19-2013 09:37 AM
almost forgot, check the throttle plate/ base of the carburetor,they come loose and create a air leak, grab the top of the carb and wiggle it to see if there is any play, if it is you can just remove it and tighten the screws from the bottom of the carb
05-19-2013 09:38 AM
Run a can of SeaFoam in the gas tank and see if it helps, I've seen that stuff do Great Things.