Jeep won't start once it gets to running temps

JustLostOne

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So i have an issue where after i drive somewhere and my jeep get gets up to temperature, when i shut it off for a few minutes it won't start. It will fire up and immediately sputter out. It seems like once it's cooled down a bit it starts back up just fine. I've actually made up wires so that i can hook the cooling fan directly to the b battery for a few minutes to cool it so it starts right up. I'm looking for any insight on what could possibly be causing this.
 

BLACKJKU

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Have you tried putting it in 4 low and tried to start it, something about it bypasses the neutral safety.
 

BLACKJKU

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So your saying the starter turns it over but it just won't start running and keep running?
 

BLACKJKU

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I wonder if your coil pack could be going bad, not sure if that will set off a CEL or not.
 
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JustLostOne

JustLostOne

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I wonder if your coil pack could be going bad, not sure if that will set off a CEL or not.
I replaced the coil pack, wires and plugs and it was still doing it. Occasionally if I try too long to start it i get the CEL light with lean condition but again it only has the problem when it's been at temperature.
 

BLACKJKU

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Does it even do it when the weather is cooler outside? Have you tried to turn on your cooling fan for a few minutes before shutting it off to see if it will start back up?
 
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JustLostOne

JustLostOne

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Does it even do it when the weather is cooler outside? Have you tried to turn on your cooling fan for a few minutes before shutting it off to see if it will start back up?
It still did it during the winter. I've thought about wiring a switch to the cooling fan so that i could turn it on whenever I need to but also don't want to have it just on a switch.
 

BLACKJKU

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The cooling fan has to be cooling some component on the engine, with the engine not running and the cooling fan on it's only cooling the radiator.

There surely isn't a sensor that tells the ECM the engine is to hot and shuts it down, but with all the other nonsense things that it does I wouldn't doubt it.
 
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JustLostOne

JustLostOne

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The cooling fan has to be cooling some component on the engine, with the engine not running and the cooling fan on it's only cooling the radiator.

There surely isn't a sensor that tells the ECM the engine is to hot and shuts it down, but with all the other nonsense things that it does I wouldn't doubt it.
There is a temperature sensor on the top front of the motor but I've replaced that also.
 

BLACKJKU

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I wonder if there's a relay in the TIPM that's getting hot, but as far off it is from the cooling the fan you wouldn't think it would do much good to cool over there.
 

franka548

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Ok , didn't know about fuel filter, but I would still check fuel pressure. It sounds like vapor lock, if the fuel pressure isn't up to snuff, it might be enough to fire the injectors, but not enough to over come vapor lock. Also make sure the fuel lines are not near an exhaust or radiator hose.
Frank
 

BLACKJKU

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I was doing some reading and found where people have been adding a extra ground to the engine usually at the alternator frame from the battery. They were having starting issues like you, I did that shortly after buying my JK because a bad ground can cause alot of issues.