xj not running properly

[race913]

I have a 1992 cherokee 4.0 aw4 auto that's not running very well under load(in gear). The exhaust is not plugged and the engine is not overheating. It feels like when you get on the gas and try to accelerate it is starving of fuel. It really struggles past 1/4 throttle. Anybody had these similar issues please give some feedback. Thanks....

 

[DaveB]

Check your fuel filter and fuel pump as a first step.

 

[Milner]

Check your fuel filter and fuel pump as a first step.

Yep, then plugs, cap, rotor, etc.
How many miles are on it? Could be time for a timing chain. Does it use any oil? Maybe a compression check? O2 sensor? Any codes?
Could be a simple problem, could be more....

 

[RockMonkey]

How do you know the exhaust is not plugged? This sounds exactly like a broken catalytic converter. Does the cat rattle?

 

[jamesgeologist]

How do you know the exhaust is not plugged? This sounds exactly like a broken catalytic converter. Does the cat rattle?

My thoughts exactly.

 

[Bart]

Sounds like exhaust to me. Maybe a throttle position sensor.

 

[Herzog]

Sounds like exhaust to me. Maybe a throttle position sensor.

agreed. A bad throttle sensor will make it feel like it has hardly any power and/or run quite rough.

 

[race913]

Checked exhaust muffler and cat for rattles. Nope, all is sound. Fuel filter is changed now. It will backfire also. Struggles to accelerate after stall speeds. Might just have to get it diagnosed and then fix it. Ugh.....

 

[78mitsu]

I'd check the exhaust a second time by unbolting where the header connects to the pipe, wire the pipe up and take it for a ride, it'll be noisy, but you'll know instantly if that was the problem.

 

[Brett]

agreed. A bad throttle sensor will make it feel like it has hardly any power and/or run quite rough.

x3 on the TPS

 

[race913]

So, it's trouble code 36:
Wastegate control circuit open or shorted
What does this mean. Details please. Thanks

 

[Rusted]

found this from a google search

wastegate control circut is a code for a turbo engine.If the van isn't
a turbo the code is no help.It would be setting the code because the
compter doesn't see the wastegate solenoid (open)


Other matches were related to the TPS problems as well. what have you done to eliminate the TPS being the problem?

 

[waynehartwig]

Yup... I agree with everything here, but I'll add...

Change the fuel filter

TPS could be bad, but it should be throwing a code if so

Exhaust could be plugged or even leaking - there is a $20 tool that will check exhaust back pressure - screws into 02 port

Timing could be off - either ignition or valve train, or both


How did the problem start? Gradually or instantly?

 

[race913]

ok. so i tried the code technique 4 more times. 36 was not it. actually was 12 and 15. which is.
12 memory standby power lost(battery or computer recently disconnected)
15 No speed/distance sensor signal. which my speed sensor plug off of t case could be loose or bad. its been off and on since i bought it though. And yes I hooked up a winch couple weeks ago and disconnected battery i believe. I can take to exhaust shop and have exhaust pressure tested. If I could locate the tps. Maybe i'll just go buy one and replace it.

 

[race913]

Fuel filter is changed and the problem happened from the time we went wheeling on sat. sat in garage until tues afterwards went to go out wheeling again. From the time it was ran on tues. it was not right. Pretty much overnight kind of deal... No signs or anything. I did nothing but let it sit in garage for 3 days. Don't understand.

 

[Bart]

TPS is on your throttle body. Get a new one from the dealer, not from Auto Zone, Checker ...

 

[waynehartwig]

ok. so i tried the code technique 4 more times. 36 was not it. actually was 12 and 15. which is.
12 memory standby power lost(battery or computer recently disconnected)
15 No speed/distance sensor signal. which my speed sensor plug off of t case could be loose or bad. its been off and on since i bought it though. And yes I hooked up a winch couple weeks ago and disconnected battery i believe. I can take to exhaust shop and have exhaust pressure tested. If I could locate the tps. Maybe i'll just go buy one and replace it.

The distance sensor is causing the code 15 - either it's not plugged in, faulty, etc. This is on the tcase where the speedo cable plugs into. Make sure it's plugged in. Does your speedo work? If so, replace the distance sensor.

Jeep part number - 5252438 - $68
EDIT: XJ and MJ are the same part; YJ and ZJ are different

In light of this, don't change the TPS yet....

 

[RockMonkey]

Please remember to updated this thread when you found the fix. It really helps others who may have the same problem in the future.

 

[Brett]

TPS is on your throttle body. Get a new one from the dealer, not from Auto Zone, Checker ...

I'll second this. I'm on the second one from Checker and it's starting to act funny again. Jeep dealer is the next stop.....

 

[race913]

Speedo plug is cleaned and re installed nice and tight. Works great now... Still runs like poop. I'm prob. gonna drop off at dealer on monday. $85 for diagnostic ugh. Oh well, atleast I will know for sure what is wrong instead of guessing and spending more money on parts that I don't need. If it's tps, I will just have to laugh.... I hope it is though. It's only like $63 to replace. so that would be $150. I can handle that ok. I will for sure let everyone know what is determined.