99' XJ Problems

[Hudson]

Sorry for all the threads, but the Jeep is currently enemy #1. I would of made the title more specific, but i honestly think this jeep is just falling apart, and in need of a lot of work.

Here is everything i'm experiencing;

- Random Stalling
- Jeep Not Going Over 3k RPMs
- Oil Pressure Is Higher Than Where It Used To Be (Used to always sit half way, now it's over.)


It used to be really hard to start, like i'd have to crank and crank and crank, and sometimes i'd even have to push down the gas pedal for it to start. About 2 weeks ago, it just died on the side of the road and wouldn't start at all, i had to let it sit for like 20 minutes, then it just turned over after some cranking. The new battery makes the engine turn over a lot faster, and i haven't experienced the hard starting yet after this.


The RPMs stop going up at 3,000. I can push the gas pedal all the way down, and it will NOT go over 3,000 RPMs. It just stops there. If i put it in park though, it will well exceed 3,000. I was trying to flex my front suspension, and i went to climb onto a rock, and my RPMs stopped at 3,000 and that was all she had. Didn't even make it up onto the rock, the RPMs just sat at 3,000 even though my foot was all the way down, it was like it wasn't even trying.

Some points after i drive it for like 5 minutes, it does this thing, where it feels like the jeeps rolls backwards while going forwards. That's the best i can explain it.

I think that might be my transmission slipping, and it need of a rebuild, but i could easily be wrong. It could also be the Torque Converter. If it is, it's a AW4 Transmission i believe. It's an Auto 99 XJ.

In the past two months, i have done this to it;

- New Oil
- New Oil Filter
- New Cap, Rotor, Plugs, Plug Wires
- New Battery
- Cleaned both grounds, and even rewired them. (Old one snapped, and i fixed it.)

I haven't tested any of the sensors, and my CEL isn't on.

I think these are mainly the culprit(s);

- Weak Fuel Pump
- Bad Coil
- Fuel Filter
- Bad CPS
- Dirty Injectors
- Possibly a slipping transmission
- Possibly a Torque Converter.

It's turning into one big headache, and costing me a fortune to try to troubleshoot.

[justtorchit]

Sorry for all the threads, but the Jeep is currently enemy #1. I would of made the title more specific, but i honestly think this jeep is just falling apart, and in need of a lot of work.

Here is everything i'm experiencing;

- Random Stalling
- Jeep Not Going Over 3k RPMs
- Oil Pressure Is Higher Than Where It Used To Be (Used to always sit half way, now it's over.)most people with a jeep wish they had your problem


It used to be really hard to start, like i'd have to crank and crank and crank, and sometimes i'd even have to push down the gas pedal for it to start. About 2 weeks ago, it just died on the side of the road and wouldn't start at all, i had to let it sit for like 20 minutes, then it just turned over after some cranking. The new battery makes the engine turn over a lot faster, and i haven't experienced the hard starting yet after this.sounds like a coil or a break somewhere causing the coil not to fire. by any chance was it a rainy day when this happened? had an issue like that and chased the issue for a long time. it was actually the connector going to the coil had a bad seal and moisture would fuck it up. that and the casing around the coil was cracked. maybe check the grounds that are on the block by the coil. seen that issue before too.


The RPMs stop going up at 3,000. I can push the gas pedal all the way down, and it will NOT go over 3,000 RPMs. It just stops there. If i put it in park though, it will well exceed 3,000. I was trying to flex my front suspension, and i went to climb onto a rock, and my RPMs stopped at 3,000 and that was all she had. Didn't even make it up onto the rock, the RPMs just sat at 3,000 even though my foot was all the way down, it was like it wasn't even trying.
Try 4 low

Some points after i drive it for like 5 minutes, it does this thing, where it feels like the jeeps rolls backwards while going forwards. That's the best i can explain it.if its the tranny slipping it will rev up while that happens. my bet is engine skipping. but that would trigger a check engine code usually. my bet is on a bad coil.... its very common

I think that might be my transmission slipping, and it need of a rebuild, but i could easily be wrong. It could also be the Torque Converter. If it is, it's a AW4 Transmission i believe. It's an Auto 99 XJ.

In the past two months, i have done this to it;

- New Oil
- New Oil Filter
- New Cap, Rotor, Plugs, Plug Wires
- New Battery
- Cleaned both grounds, and even rewired them. (Old one snapped, and i fixed it.)

I haven't tested any of the sensors, and my CEL isn't on.

I think these are mainly the culprit(s);

- Weak Fuel Pump
- Bad Coil
- Fuel Filter
- Bad CPS
- Dirty Injectors
- Possibly a slipping transmission
- Possibly a Torque Converter.

It's turning into one big headache, and costing me a fortune to try to troubleshoot. ,shoulda bought a prius

[Hudson]

I would quote that entire thing, but it would take up too much space.

I don't think it was raining that day, but i could be wrong. I think i'll replace the coil, as i've never replaced it, and i don't think it could hurt anything.

Oh, never even thought of 4lo. I have so much to learn.

You'd say my transmission is fine? That's a huge relief if that is true. I'll get the coil swapped out and report back.

Nope. I'd never buy a prius. There is something about driving that Jeep that is indescribable. Every time i drive it, it just makes me happy. It's in a league of its own, and it's fucking awesome.

[justtorchit]

I would quote that entire thing, but it would take up too much space.

I don't think it was raining that day, but i could be wrong. I think i'll replace the coil, as i've never replaced it, and i don't think it could hurt anything.

You'd say my transmission is fine? That's a huge relief if that is true. I'll get the coil swapped out and report back.

Nope. I'd never buy a prius. There is something about driving that Jeep that is indescribable. Every time i drive it, it just makes me happy. It's in a league of its own, and it's fucking awesome.

your tranny is probably fine... it dosent rev up when you have that feeling right?
throw a tranny cooler on if you havent already, and maybe do a good flush. without gears you are putting alot of stress on the tranny and when climbing anything use 4 low. thats what its there for.....

[92xjlaredo]

You say the engine won't rev past 3k on the tach? Does it spit and sputter at that range or does it just stay steady at 3. I had a catalytic converter plug up really bad and it did that to me. Only occassionally it went past 3k and ran really bad. But I do believe it would throw a check engine...I too had very similar problems with an old XJ I had, so i know how frustated you can get.

[ninetysix-ex-jay]

I used to have to put the peddle to the floor to start mine. Turned out to be the temp sensor on the front of the motor.

[Lawn Guyland]

im sorry, all i could think of when i saw this title was this

[ame]http://www.youtube.com/watch?v=SSmoJ5w0sCI[/ame]

[Bigbike]

BAHAHA I legit was just thinking of that song when I opened this thread.

[customcreationsllc]

Sounds like it is broken.
Isn't working as a mechanic fun
Have you actually tested anything yet or just felt like coming online and complaining.

...
In the past two months, i have done this to it;

- New Oil
- New Oil Filter
- New Cap, Rotor, Plugs, Plug Wires
- New Battery
- Cleaned both grounds, and even rewired them. (Old one snapped, and i fixed it.)

These wouldn't have anything to do with your problem.

I haven't tested any of the sensors, and my CEL isn't on.

I think these are mainly the culprit(s);

- Weak Fuel Pump
- Bad Coil
- Fuel Filter
- Bad CPS
- Dirty Injectors
- Possibly a slipping transmission
- Possibly a Torque Converter.

A lot of things can be the problem or it can be a couple things you can test just about everything.
Transmission problem doesn't make any sense
CPS doesn't make any sense they either work or don't and since it does start sounds like it works. and you can easily test that if you have the right tools.

Do you have a nice hot spark?
Do you have good fuel pressure?
Do you have compression?
Do you have signal to the injectors?
MAP sensor
O2
All that stuff is very easy stuff to check.

I've seen some weird stuff but it is probably just something straight forward.


It's turning into one big headache, and costing me a fortune to try to troubleshoot.
All cars break, expensive doesn't sound like you spent any real money on it yet. You cannot count maintenance parts.

[customcreationsllc]

[ame]http://www.youtube.com/watch?v=s_0THARUP9A&feature=player_embedded[/ame]

[Hudson]

your tranny is probably fine... it dosent rev up when you have that feeling right?
throw a tranny cooler on if you havent already, and maybe do a good flush. without gears you are putting alot of stress on the tranny and when climbing anything use 4 low. thats what its there for.....

It actually doesn't happen a lot. It seems to only do it within the first 5 minutes of driving, after that it never happens. No, the RPMs do not go up when it does that. I haven't put a tranny cooler on it yet, but if i did, how much would that cost? I'm going to regear once i put 35s on it. I can't seem to get into 4 lo for the life of me. I tried it from neutral and in drive, but it still wouldn't go in. I pushed the shifter to the right and pulled, but nope.

You say the engine won't rev past 3k on the tach? Does it spit and sputter at that range or does it just stay steady at 3. I had a catalytic converter plug up really bad and it did that to me. Only occassionally it went past 3k and ran really bad. But I do believe it would throw a check engine...I too had very similar problems with an old XJ I had, so i know how frustated you can get.

It's at a steady three, however i never changed the cat, i should probably look into that. Thanks for the suggestion.

im sorry, all i could think of when i saw this title was this

http://www.youtube.com/watch?v=SSmoJ5w0sCI

I feel as if i'm currently having 99 problems.

Sounds like it is broken.
Isn't working as a mechanic fun
Have you actually tested anything yet or just felt like coming online and complaining.

Yes, tons of fun working as a mechanic. I haven't tested a damn thing, i just felt like coming online to complain and let it out.

What tools would be needed to test the CPS? I can't even find the damn thing. I always heard that the CPS can act up once the engine gets warm.

Didn't check for spark, didn't check the fuel pressure (don't have a gauge, so i'll have to bring it to a parts store), didn't check the compression, don't have those gauges either. Not sure how to check to see if i have a signal to any of my sensors. Care to fill me in? I also read everything to "check the wiring". Does that simply mean to see if the wire is frayed?

[justtorchit]

coolers are cheap and easy. i just suggest that for keeping the tranny cool. nothing to do with any of your problems

for the 4 low issue: try adjusting your linkage. dont ask how, get under and figure it out yourself.

your 3 grand rev issue has nothign to do with the cat. simply sounds like you tried climbing up something and your jeep said fuck you put me in 4 low

next time it dies. get out instantly, pop the hood and check for spark. if you have no spark then its not a fuel issue. then unplug the coil and check for power at the connector. nothing there, then start looking into the cps or other things.

work your way back through the system

[customcreationsllc]

To check a CPS you need a oscilloscope basically a graphing mulit meter.
I like the snapon vantage MT2400 you can find the old ones cheap on e-bay
a CPS is a hall effect sensor. you will get a square wave after every tooth. basically if you have a signal it is working.
takes 2min to check. you just pierce the signal wire and ground and start it up.
The CPS should be on the top of the bell housing.
Same goes with any sensor the Vantage tells you where and how to test each sensor.
You can check MAP sensor just check the resistance and pull a vaccum. Just like testing the TPS just check resistance and rotate throttle.
You can test temp sensor cam sensor whatever you want.
1 tool any good diagnostic mechanic must have, without it it is just guessing.

Fuel pressure you need a fuel pressure gauge and you have a valve on the fuel rail again takes 2 min. You can get a cheap one.

You can drive around with everything on and when problem happens see what you are missing.

the spark just need to pull the wire off and look for a nice hot spark.
You can use a timing light to check spark if the light is flashing it is sparking.

Compression is a little tricky but you need fuel/air spark and compression to make an engine run.

To check for clogged cat just unbolt it and drive see if it is any better.
Real way is to pull out the O2 and install a pressure gauge.

Mechanics have thousands of the dollars in tools think of them as an investment.
You shouldn't need to guess what is wrong
You can just pay a mechanic to fix it.

Basically if your transmission shifts normal doesn't slip and no noise it is probably fine.
Cooler you can keep your trans the better. coolers are around $60 take 30min to install.
best to go through the rad first then through the new air cooler. they just zip tie to the radiator.

AW4 are pretty forgiving.

To shift into 4low try neutral engine off.
Make sure the linkage is free and adjusted you can disconnect and rotate the lever with pliers to make sure the T-case is OK.
did you install a SYE? did you cut down the shifter shaft?

Really should use low range.

[Hudson]

coolers are cheap and easy. i just suggest that for keeping the tranny cool. nothing to do with any of your problems

for the 4 low issue: try adjusting your linkage. dont ask how, get under and figure it out yourself.

your 3 grand rev issue has nothign to do with the cat. simply sounds like you tried climbing up something and your jeep said fuck you put me in 4 low

next time it dies. get out instantly, pop the hood and check for spark. if you have no spark then its not a fuel issue. then unplug the coil and check for power at the connector. nothing there, then start looking into the cps or other things.

work your way back through the system

I'll look into a tranny cooler once i get these problems all sorted out. When the daylight shows up in like another two hours, i'll go out there and begin tinkering with it. I should be able to get it moving with a bottle of Tri-flow.

Will do, wasn't sure how to check for spark until custom chirped in and filled me in. Will make sure to check next time. My only question with this is, if i need to check for spark, don't i need someone with me to turn the ignition while i check for spark, or is there a way to do this on your own?

To check a CPS you need a oscilloscope basically a graphing mulit meter.
I like the snapon vantage MT2400 you can find the old ones cheap on e-bay
a CPS is a hall effect sensor. you will get a square wave after every tooth. basically if you have a signal it is working.
takes 2min to check. you just pierce the signal wire and ground and start it up.
The CPS should be on the top of the bell housing.
Same goes with any sensor the Vantage tells you where and how to test each sensor.
You can check MAP sensor just check the resistance and pull a vaccum. Just like testing the TPS just check resistance and rotate throttle.
You can test temp sensor cam sensor whatever you want.
1 tool any good diagnostic mechanic must have, without it it is just guessing.

Fuel pressure you need a fuel pressure gauge and you have a valve on the fuel rail again takes 2 min. You can get a cheap one.

You can drive around with everything on and when problem happens see what you are missing.

the spark just need to pull the wire off and look for a nice hot spark.
You can use a timing light to check spark if the light is flashing it is sparking.

Compression is a little tricky but you need fuel/air spark and compression to make an engine run.

To check for clogged cat just unbolt it and drive see if it is any better.
Real way is to pull out the O2 and install a pressure gauge.

Mechanics have thousands of the dollars in tools think of them as an investment.
You shouldn't need to guess what is wrong
You can just pay a mechanic to fix it.

Basically if your transmission shifts normal doesn't slip and no noise it is probably fine.
Cooler you can keep your trans the better. coolers are around $60 take 30min to install.
best to go through the rad first then through the new air cooler. they just zip tie to the radiator.

AW4 are pretty forgiving.

To shift into 4low try neutral engine off.
Make sure the linkage is free and adjusted you can disconnect and rotate the lever with pliers to make sure the T-case is OK.
did you install a SYE? did you cut down the shifter shaft?

Really should use low range.

I'll ask around and i'll see if anyone has a meter that would be able to check all of my sensors. It would be much nicer than having to go out a buy one, even though it would defiantly come in handy in the future.

I think i'll go out and buy a fuel pressure tester, i think i can get one for like 20$ from harbor freight, and it should work fine for my purposes.

I also think i might have a compression tester somewhere around here, i'll go looking for it.

Thanks for all these tips by the way, it's truly nice knowing the correct way to do something. I've learned damn near everything i know about cars from forums such as this one. Never would of even thought about throwing a pressure tester in the cat to see if it was clogged.

I'll begin toying around with the adjuster on the T-case when the sun breaks and report back on that. No, i didn't install a sye, and i didn't cut down the shifter shaft. I'll try how you mentioned to get it into 4lo, if it doesn't work, i'll begin tinkering with the adjuster.

Once again, thanks for all the assistance, i really do appreciate it.

[Hudson]

Just went to harbor freight, and bought a fuel pressure gauge.

My fuel pump is working up to par. It stays at about 50PSI at idle, and about the same when i rev the engine.

I also drove to CVS today, and it ran fine, except for when i got to CVS, i put it in park and let it idle, and the second i took my foot off the gas, the engine stalled out.

*****EDIT***** Left the fuel pressure gauge on for about 30-45 minutes, and the pressure dropped from like 45-46(where it started) to 30. Normal?