Can it be the catylic converter?
My jimmy shuts off when it gets hot what can cause this to happen? on 1998 GMC Jimmy
I would look at the ignition system, most likely an ignition module or distributor pick-up coil. Look up any check engine light codes, that will also help.
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I had a 1995 jimmy,its probably vapor lock because mine did it until I changed thermostat,water pump and that solved the problem