TJ is peak. Anyone tried to de-modernize theirs?


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It is frustrating that the TJ is so vulnerable to problems with its 'computer'. It seems to me that a computer represents the antithesis of what a Jeep is supposed to be. Rugged, utilitarian, able to be repaired in the field with blood, sweat and duct tape. I would like to be able to brag that my Jeep can go anywhere and do anything without having to add "...unless the computer shuts it down and turns it into a useless, albeit still sexy, pile of metal".

In the old days we didn't even have radios or seat belts. Personally I have removed one and have contemplated the latter because it's too damn loud to enjoy music (and I wanted the space for a HAM radio) and if you get into an accident in a Jeep a seat belt will not help you. They are not safe vehicles, and that's fine with me. However, my recurring PCM problems and the fact that they are a pain in the a** to acquire has only bolstered my desire to remove the computer altogether from the TJ.

Yes modern computers make cars more efficient etc etc. But seriously I get 10 MPG. That's the same as 70's-era CJs. The '81 got 15mpg (I don't think the '81 had a computer). Maybe my '02 is supposed to get more but not much. My JK only got 14mpg.

I could get an older Jeep, but the TJ is peak and the 4.0 is bulletproof. Now, I imagine I could swap my automatic transmission for a manual (or just get a manual), swap in a distributor, and a few other things, and be free of all these mother loving sensors and computers.

Anyone tried to de-modernize their TJ?
 
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bromel

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The TJ's computer is very primitive by modern standards, and the only ones that tend to have problems are the 05 and 06 model years. I think your 02 PCM problems are the exception to the rule unfortunately. I imagine you'd have to rig up a carburetor if you truly want to go fully analog.

Have you tried getting a new PCM?

Also I can't imagine you would be able to pass yearly emissions without an OBDII computer...

 
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Airjunky

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Never had a problem with the computer on the TJ, or any other car I've owned. Sensors, yes, but not the computer.

I grew up working on carbs, points, condensers, old school. And have fully embraced EFI & electronic ignition. I've had way less problems.

I can easily hear (and feel) the stereo. And go figure, I get a lot better than 10 mpg too.
 
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The TJ's computer is very primitive by modern standards, and the only ones that tend to have problems are the 05 and 06 model years. I think your 02 PCM problems are the exception to the rule unfortunately. I imagine you'd have to rig up a carburetor if you truly want to go fully analog.

Have you tried getting a new PCM?

I got a reman a few years ago because the alternator wasn't charging the battery. Apparently the voltage regulator is inside the PCM. Then recently the PCM drivers went out for injectors #4, 5 and 6 and now it just dies unless I keep the RPMs up and it drinks gas. And the cluster flickers.

It's not 'usual' for the PCM to go out, especially twice in a few years but it happened.

I would love a new PCM but I can't find one with my specific code. Flagship has a dozen for the '02 but none with my code. So I'm having it 'repaired'. Well, I had it repaired but it didn't fix it so I'm having it repaired again.
 

T_Hase89

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I’d rather take my chances with my seatbelt on versus off. Chances of survival even in an “unsafe” Jeep are much higher being secured in the vehicle than being tossed out a door or top or windshield.

And I’ve never had a PCM issue in any vehicle ever. The ability for it to self adjust versus constant tuning of a carb for different fuel types (winter - summer), weather conditions etc just seems better to me.
 
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qslim

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and if you get into an accident in a Jeep a seat belt will not help you. They are not safe vehicles, and that's fine with me
What? The TJ may not be the safest vehicle on the road but it's not like you're a Russian Cosmonaut in the 60's and the seatbelt is totally worthless.
 
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I’d rather take my chances with my seatbelt on versus off. Chances of survival even in an “unsafe” Jeep are much higher being secured in the vehicle than being tossed out a door or top or windshield.

And I’ve never had a PCM issue in any vehicle ever. The ability for it to self adjust versus constant tuning of a carb for different fuel types (winter - summer), weather conditions etc just seems better to me.
I'll give you the seat belt thing. But Jeep still has a one star safety rating. Even the new ones. Which, again, is fine by me.

Have you ever thought you had PCM problems but it turned out to be something else?
 

tworley

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Then recently the PCM drivers went out for injectors #4, 5 and 6 and now it just dies unless I keep the RPMs up and it drinks gas. And the cluster flickers.
Have you checked the actual injectors? Its easy to point the finger at the PCM when having trouble solving an issue.

Similar to Jerry, 23 years and my PCM is still working fine. I thought there was an issue with it once, but my problem stemmed from a poorly seated wiring harness that was causing intermittent power to be sent to the CAM and CPS sensors.

If your PCM is truly bad (it does happen, but it is rare), try wranglerfix. He has been getting positive reviews around here.
 

SecondChanceTJ

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It is frustrating that the TJ is so vulnerable to problems with its 'computer'. It seems to me that a computer represents the antithesis of what a Jeep is supposed to be. Rugged, utilitarian, able to be repaired in the field with blood, sweat and duct tape. I would like to be able to brag that my Jeep can go anywhere and do anything without having to add "...unless the computer shuts it down and turns it into a useless, albeit still sexy, pile of metal".

In the old days we didn't even have radios or seat belts. Personally I have removed one and have contemplated the latter because it's too damn loud to enjoy music (and I wanted the space for a HAM radio) and if you get into an accident in a Jeep a seat belt will not help you. They are not safe vehicles, and that's fine with me. However, my recurring PCM problems and the fact that they are a pain in the a** to acquire has only bolstered my desire to remove the computer altogether from the TJ.

Yes modern computers make cars more efficient etc etc. But seriously I get 10 MPG. That's the same as 70's-era CJs. The '81 got 15mpg (I don't think the '81 had a computer). Maybe my '02 is supposed to get more but not much. My JK only got 14mpg.

I could get an older Jeep, but the TJ is peak and the 4.0 is bulletproof. Now, I imagine I could swap my automatic transmission for a manual (or just get a manual), swap in a distributor, and a few other things, and be free of all these mother loving sensors and computers.

Anyone tried to de-modernize their TJ?
Please do wear the seatbelt! It's there for good reason!
 
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Chris

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Why not just buy a CJ?

The PCM thing is dramatically blown out of proportion. For all the stories you read about, there are hundreds of others with no issues whatsoever.
 
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Have you checked the actual injectors? Its easy to point the finger at the PCM when having trouble solving an issue.

Similar to Jerry, 23 years and my PCM is still working fine. I thought there was an issue with it once, but my problem stemmed from a poorly seated wiring harness that was causing intermittent power to be sent to the CAM and CPS sensors.

If your PCM is truly bad (it does happen, but it is rare), try wranglerfix. He has been getting positive reviews around here.
Well all the details are on another thread. Not sure how to link to that...

Yes I replaced the injectors and connectors, and the wiring all tested perfect power and continuity.

That's interesting about the poorly seated wiring harness. Where exactly was it loose?
 
OP
J
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What? The TJ may not be the safest vehicle on the road but it's not like you're a Russian Cosmonaut in the 60's and the seatbelt is totally worthless.
That's funny I always make jokes about Russian cosmonauts. I would like to note however that they got to space first with nothing but vodka and duct tape. Their seat belts may not have been so bad.

And I think we're getting off topic here. I'm not telling people not to wear their damn seatbelt. All I said was Jeeps aren't safe and that's perfectly fine with me. I'm concerned with other things.

Did the Willys have seatbelts?
 
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J
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Please do wear the seatbelt! It's there for good reason!
Not telling people how to drive. I drive slowly and carefully and haven't worn a seat belt in years. Again, I'm not advocating that, nor am I saying that because nothing has happened to me then it's fine to do. I mentioned the seat belt thing to emphasize how serious I am about not having superfluous sensors and computers.

Just a little glib humor
 

bedhed

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It's worth mentioning from the start that I have an '06 model, but I wanted to comment to say that I've had similar feelings/thoughts about mine. Even with mine being an '06, I'm on the fence with those thoughts though.

When I start to think how much I'd like to remove the computer annoyances from the equation, I think back to what's already been mentioned. Compared to modern vehicles, our computer controlled components are pretty minimal. With that said, aside from the ridiculous "all-in-one" route they took with the computer, we would have to step quite a ways back in time, and remove the computer all together. Like what's already been mentioned as far as that goes, the idea of having to tinker on a carb isn't something I would prefer to do.

That thinking turns into me just wishing that they would at least separated the different control modules.

The progress and outcome of doing what you mentioned would be interesting to see though.
 
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freedom_in_4low

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I went through a phase where I was more concerned than the average person about things like an EMP or a coronal mass ejection frying every piece of electronic on earth and leaving my Jeep useless. But, I regularly drive my TJ in elevations ranging from 4,000 to 10,000' with jaunts up near 13,000' a couple of times per year. I would HATE having a carburetor.

I do read the threads on this forum about people having various issues with the more advanced electronics in their later TJ's, and I always think how glad I am to have a 99 with a distributor and an AX15.
 
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