Jeep cutting off

[JricePlayzHD]

I have a 97 TJ 4.0 standard with 73,000 miles on it. When I am driving it wants to stall then cuts back on. The rpm gauge & speedometer will drop to 0 until it comes back. When it stalls, sometimes the rear tires will lock up until I kick it in neutral. When it cuts off, sometimes it will take a few minutes before it will start back up and it is acting like it’s flooded. The fuel pump kicks on just fine. I was told to clean the throttle body, which I have done.

It was throwing engine codes for cylinder 4 & 6 misfire and throttle position sensor. I have since reset the CEL and it is still doing it. This time when it did it, it did not throw a code.

So far I have replaced the crank shaft position sensor, throttle position sensor, plugs and distributor.

The transmission is needing to be rebuilt. I was told it was the synchros. 3rd & 4th gear grinds when going in gear.

Any ideas?

 

[Steel City 06]

I would check the entire battery/charging system.

Take each battery and alternator terminal apart, and clean them up with emery cloth or steel wool until they are shiny. Any contacting metal should be very shiny. Reassemble them tightly. Look for any breaks in the line. If there is any discontinuity occurring, it could cause similar issues to what you describe.

Be sure to also clean the ground points, such as where the battery is grounded to the block and to the body, and where the alternator grounds to the engine.

 

[JricePlayzHD]

I would check the entire battery/charging system.

Take each battery and alternator terminal apart, and clean them up with emery cloth or steel wool until they are shiny. Any contacting metal should be very shiny. Reassemble them tightly. Look for any breaks in the line. If there is any discontinuity occurring, it could cause similar issues to what you describe.

Be sure to also clean the ground points, such as where the battery is grounded to the block and to the body, and where the alternator grounds to the engine.

If it was the charging system, wouldn’t it make the radio cut off as well?

 

[Steel City 06]

If it was the charging system, wouldn’t it make the radio cut off as well?

It could, depending on where exactly the bad connection is. If the battery post connection is bad, it could cause the radio to go out. However, if the engine block ground is bad, that could allow the radio to still play while none if the engine systems work.


This is just one possibility in many. I don't have high confidence that that would fix your issue, but it's an easy and inexpensive place to start.

 

[Dlo250]

I had same problem. Jeep was also jerky jerky while driving
Replaced Crankshaft position sensor w mopar one.
Changed out both O2 sensors with NTK.

runs perfect now.

 

[JricePlayzHD]

I had same problem. Jeep was also jerky jerky while driving
Replaced Crankshaft position sensor w mopar one.
Changed out both O2 sensors with NTK.

runs perfect now.

When you say jerky, do you mean it’ll jerk back and forth like is getting hung up on something?
My jeep is doing that exact thing.

 

[Dlo250]

Yep, hang up is exactly what it felt like to me.

Initial thought was fuel pump cutting off. Cruised this forum and came across mopar crankshaft pos sensor and NTK oxygen sensors, so I changed them.

Having replaced O2 sensors on other cars, I think the O2 sensors have a much larger influence on fuel/air mix in the Jeep than in other cars.

Replacing these parts made a drastic difference and fixed my problem.
Good luck.

 

[JricePlayzHD]

Yep, hang up is exactly what it felt like to me.

Initial thought was fuel pump cutting off. Cruised this forum and came across mopar crankshaft pos sensor and NTK oxygen sensors, so I changed them.

Having replaced O2 sensors on other cars, I think the O2 sensors have a much larger influence on fuel/air mix in the Jeep than in other cars.

Replacing these parts made a drastic difference and fixed my problem.
Good luck.

Awesome thank you. Where did you get your crankshaft sensor from?
Did you get any engine codes from this issue?

 

[Dlo250]

Went with mopar America. They also have the ability to put your vin in at time of purchase and they will verify you get the correct item.
Got the o2 sensors from rock auto. If you’re gonna do those, start the PB blasting now!