Howdy ya,ll
My dad has a 4.0, auto 4x4 that has a problem, it is retarding the throttle , it hits 2000 rpm and cuts out like it ran out of fuel, makes a couple sounds like a internal backfire and then roars to life. No engine codes and will do it when ever it likes below 45 mph.
We have replaced alternator, tps and the air doojickey on the throttlebody. Since it has no check engine lite or trouble codes, no one can fix it. Anyone have an idea what is causing this problem ?
It also will do it when it is cold, hot and vice versa on the outside temps are cold or hot.
We are stumped. <img src="/forums/images/graemlins/zombie.gif" alt="" />

If it acts like it is running out of gas...it prolly IS!!
Check for gasoline filters, fuel pump and fuel pump intake SCREEN in the tank.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

If that is the case......why isnt it consistent ?

It could be the O2 sensor too. Mine would stumble when driving and it would go away at wide open throttle, until the sensor finally got bad enough to set the fault code. I would see if you can get someone to actaully look at the engine data while it does it, and not just look at the fault codes.

Sean

We have had it at 2 different repair shops and it wont ever do it for them, now they just start it and move it around so it nevers messes up for them.

The Ox sensor sounds more logical than a fuel problem as it is sporadic. BUT YOU NEVER KNOW.
Thanks for the info ya'll.

Check the carburetor.

Never mind - I think 1996 was the last year Jeep used a carburetor (some kind of electronic carburetor) and it was known for problems. But that was before your Jeep's time.

<img src="/forums/images/graemlins/smile.gif" alt="" /> merry Christmas anyway!

jeep cherokee xj hasnt had a carb since the 80's

you said you replaced the tps,Is it properly set? I don't know if the newer ones are adjustable,but my 89 is.i dont know the readings right away or even if it would be the same as mine as well as the procedure to adjust it.Also the )2 sensor don't always throw a code, when mine went it never did either. It couls also be that the iac (idle air control)is sticking. clean the enire throttle body. could also be a partially clogged cat. as you can tell there are numerouse things it could be. just start at one end and start working back until you find the problem.

Pardon me - Cuervo25 is correct. I drove an Army jeep in 1981 and 1982 and it was always the carburetor. (Now I have and love a 2006 TJ and have no problems with anything -it is super.)

There was a problem electronic carburetor (started with B, maybe Cuervo25 knows) in Jeeps for a few years in YJs but that must have ended earlier than I thought.

Try this, if you haven't already - check the electrical grommet connectors at the top of the fuel pump module and see if they are plastic. If so, there could be a fuel leak because of corrosion. In 2006, a 1998 Jeep Cherokee recall was issued for this problem.