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Jeep is Bipolar or needs an exorcism

1996 4.0 with new battery starts often starts fine, but then… sometimes hot or cold it throws a total hissy fit. Like a kick back or detonation it stops cranking or the whole engine shudders. When it starts it idles rough a few seconds and then is fine (like my first wife). This wore out 1 starter. I replaced the idle air valve, computer, and checked the fuel injectors for leaks, and tried a lot of prayer. No lights come on. The water reservoir loses some water and I thought it might be a head gasket or block problem but he oil is clean and no smoke in the exhaust. I pulled the thermostat to flush the system before using K&W nano to seal a leak n case fluid is getting in in a cylinder.
Am going to check the plugs to see if any are wet.

Anyone seen this problem?

If it’s kicking back, I would suspect ignition. What shape are your cap rotor and wires??

You don’t say how many miles are on the vehicle, but a stretched timing chain can cause this problem. This then causes both the ignition and valve timing to be off.

Here’s a Jeep 4.0 liter engine with only 60,000 miles on it and the timing chain is already stretched.


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