[Ididthatmilitarything]

Like I said I just picked up a 99 XJ.

4x4
4.0
Auto
156k miles

I only paid 800. Body is pretty good. A couple dents. Glass is good. It has a hack job exhaust where they cut the muffler out and put the wrong size exhaust pipe so not at both ends it is rinckled and leaks. This will be question 1. The heat only blows out of the defroster, I need to check the vacuum lines. The other problem I have is in the trans. The shifting is off. Sometimes it clicks through the gears perfectly fine. Other times it will shift early and then no drop in to over drive. This will be question 2.

My plans with this vehicle are to replicate a specific jeep I found and I attached it. I am planning on going with a 4.5 lift. I will not need long arm as it will not be my trail rig. I am currently looking for another to build my trail rig.

So gents.
Question 1-
Can I run the exhaust with no muffler and not get a caution from the downstream O2 sensor?

Question 2-
Should I waste the time having a diagnostic done or just replace the trans?

Thank you for any input,
Michael

 

[lawagoneer]

The transmission in the Cherokee is the AW4. They are insanely strong and very understressed in the Cherokee. It is worth being checked. It may only need a filter and fluid change and throttle valve cable adjustment.

The other possibility is there is some sensor problem. The transmission computer gets input from some engine sensors. Is your check engine light on?

 

[Ididthatmilitarything]

Yes the check engine light is on. I thought it was he NSS because my reverse lights are not working, it is slow to start, and will not hit overdrive at times. I have already don't a filter change and put new fluid in. It has a complete tune up. Everything but the fuel filter.

 

[Gluckmysock]

You can run without a muffler. The downstream O2 sensor is in the cat.

Have you tried adjusting your TV cable?

I was getting reverse lights that worked whenever they felt like it, and also the crank time seemed a little long. I followed a write-up for cleaning the NSS and it solved both my problems. You can try starting it in Neutral and see if it starts quicker.

 

[Ididthatmilitarything]

I have not adjusted it. I will try the neutral start this morning. Like I said I just bought it and I am trying to diagnose and fix things as I go prior to the lift and paint. One thing I just noticed yesterday is that once it starts it will have a clean idle then it will go into a 5 second studder and rough idle then it will clear up. I have a code for an EVAP sensor. I do not know if these things are connected or not but I was planning on just putting checks in the box till its gone.

 

[eagerjeeper]

Nice rig!

 

[muddeprived]

I have not adjusted it. I will try the neutral start this morning. Like I said I just bought it and I am trying to diagnose and fix things as I go prior to the lift and paint. One thing I just noticed yesterday is that once it starts it will have a clean idle then it will go into a 5 second studder and rough idle then it will clear up. I have a code for an EVAP sensor. I do not know if these things are connected or not but I was planning on just putting checks in the box till its gone.

is it a evap sensor or evap leak code?

 

[Ididthatmilitarything]

There was a code for EVAP. I have done a bunch of work to it so who knows it may have just been a loose connection. The code is gone. Now there is a trans caution. I am going to clean and adjust the NSS. The neutral start did not affect the start. It is still slow. Update will come.

 

[Bradleyholtz]

I’m running no muffler on my 99 limited. Cut it off about an inch from the O2 sensor behind the cat. I’ve been running it like that no extra pipe or anything for a few months now and have no issues. No check engine lights. Starts up with no hesitation and no power loss

 

[redskylark]

Impressive rig! Got any updates regarding it?