'96 XJ sport 4.0 5 speed 200k+ miles.

When the temp gets to 210 the engine will die and not start untill it cools down in the 140-160 degree range. Also the clutch seems to shift harder (takes force to shift from gear to gear) as the temp increases. I don't think they are related but???

1. I just put a new upstream O2 sensor in.
2. The catalytic converter was stolen when I bought it and I just have a pipe in it's place going into a cherry bomb muffler.
3. I replaced the thermostat with a 195 degree unit.
4. when it dies it appears to have fuel at the rail as I can push in on the shrader valve and get a good supply of gas.
5. If I open the hood when it dies it cools quicker and starts quicker.
6. With the new thermostat it runs right below the 210 mark on the gauge.
7. It has never died on the highway while I'm moving at speed but has died in town in traffic.
8. If I park it at the "normal" temp if it doesn't have time to cool it won't start.

I have checked everything I can I hope somebody has a good idea of what to check next.

 

I run a 180* t stat in mine and run about 180 195. What does it do when it dies? Does it sputter or anything?

 

Doesn't really give any warning it will just shut down almost like switchiing off the key.

 

Ignition coil

 

When ignition coils start to go bad the heat will break them down till they will no longer make spark.

 

Would it do it at that one specific temprature?

 

Not really the temp of the motor but the coil, produces its own heat naturally. This may seem like the motor but the coil is heating up at the same time. Get one from a auto part store swap it out( not hard at all). If it does not fix it take it back.

 

I really really believe this is your problem. Happened to me on my tj and I wanted to set it on fire. My good friend who is ase mech explained the therory and was totally correct, I is also a "Jeep thing" as jeep have higher under hood temp than most vehicles.

 

one thing that has not been addressed yet is your transmission.

It is time for a transmission fluid change. But here is the crappy part....

Noone makes GL-3 (and hardly anyone makes GL-4) but Redline and Napa has a light duty GL-3 that is great for doing flush's becuase it only comes in a gallon and is cheap!


so look on Redlines website for there gear oil and it wil be like $45 + shipping.

You can not use a GL-5 gear oil as it eats away at our brass syncros....


It is not hard to change. And if the gear oil comes out in any color BUT clear then i suggest getting 2 gallons of napa gear oil and doing a trasnmission flush

 

crank sensor

 

x2