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97-06 Jeep Wrangler TJ ECU / PCM Tuning Options


Chris

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If you have a 97-06 Jeep Wrangler TJ, you've probably heard lots of bullshit rumors across the internet about how our PCMs (ECUs) are locked, can not be tuned whatsoever, and there are simply no options for accessing the PCM.

Well, I'm here to dispel that stupid rumor and whoever started it. This is 100% untrue. While there may not be as many tuners for our PCMs as there would be for LS series GM engines, there are still plenty of tuning options out there for our TJs. Below I am going to compile a list of the tuning options that are guaranteed to work. Keep in mind that the crappy tuners like Superchips and Diablo Tuners DO NOT work for Tis, only JKs and newer.


Tuning Software
Syked ECU Tuning (for 97-04 TJ models)​
Syked ECU Tuning offers a complete tuning software suite to fully access the PCM on all 97-04 Jeep Wrangler TJ models.​
HPTuners (for 97-06 TJ models)​
HPTuners is very big in the GM LS tuning scene, but also the Mopar tuning scene as well. Their MPIV2 in combination with their VCM Suite gives you full access to the PCM on all 97-06 Jeep Wrangler TJ models. It does not have the ability to access 97-06 models. For more information on the HPTuners setup see my review here: HPTuner MPVI2 & VCM Suite Review: 100% Full PCM Access For 2005-2006 Jeep Wrangler TJs (at the time of writing this, HPTuners only offered access to 05-06 PCMs, however, that has changed and they now provide access to all 97-06 PCMs.)​

Tuners
Performance Dyno (can tune 05-06 models)​
Josh uses the HPTuner software and can remotely tune any 05-06 model TJ. In order to have Josh tune your TJ, you'll need the HPTuner MPVI2, as well as a wideband O2 sensor. You can see my review on the HPTuner setup here: HPTuner MPVI2 & VCM Suite Review: 100% Full PCM Access For 2005-2006 Jeep Wrangler TJs
Flyin' Ryan Performance (can tune all 97-06 models)​
Ryan uses SCT to tune all 97-04 models and HPTuners to tune 05-06 models. Like Josh, he can tune remotely, so you can be anywhere in the world and still have him do your tune. @Alex0413 has nothing but good things to say about the tune he received from Ryan for his supercharged TJ.​

Conclusion
Why am I posting this? Because there has been a long standing rumor in the TJ community that these PCMs could not be tuned by anyone, and that they were effectively locked. Well, a little detective work has led me to the right place, because I'm finally putting this myth to rest. It would appear that all hope is not lost for the ability to tune our TJs after all.
 
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Drizit

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Now that's cool as hell. I'm going to have to take a look at those supercharger kits... And then figure out how I get insurance for it.

--
There must have been a time
when we could have said no.
 
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Chris

Chris

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Now that's cool as hell. I'm going to have to take a look at those supercharger kits... And then figure out how I get insurance for it.

--
There must have been a time
when we could have said no.
They're intercooled as well. He was telling me they put down close to 300 ft/lbs of torque on the dyno at 9 psi, which is what they safely run on a stock 4.0.
 
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Chris

Chris

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Holy crap @Chris! That's the score of a lifetime right there. Good show...
I agree! With full access to the ECU, you can disable things such as evap systems, SKIM, and a host of other things that we have no control over. I've been searching for something like this for a long time now, I'm just glad I was able to get in-touch with the right people.

I'm going to have them disable all the emissions on my PCM, so I'll report back once that's done. I want to remove it all, regardless of whether it smells like unburned fuel or not. It's not a daily driver, and in my mind it's just less things to go wrong.
 
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Chris

Chris

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Extra points if they can disable that useless, annoying "shift" light. That would be worth the price of admission all by itself. Bugs the crap outta me.
Oh yeah, I forgot you manual transmission guys have those! I'll bet it's possible. I shot them an email asking if they could give me a general idea of what features can be enabled / disabled on the PCM. Hopefully I'll hear back tomorrow!
 

Alex01

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Nice find. With the cost of that system I would be shopping for quotes on a v8 swap.
 

2004X

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I have no experience with superchargers, but would love a little boost of power. Is this something for a DIYer? Obviously the ECU needs tuned, but what about the hardware installation? Any concerns of engine damage or life? How much could a person gain?

Second thought - could the speedometer be adjusted to larger tire size with the ECU tuning?
 

psrivats

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This is fantastic news. Always good to know such experts. I have a roo of respect for these guys who do good work on older cars in general. Bonus news is that they are in Oregon!

I wonder if they can do something about the 0.69 OD in the 42RLE.

Thanks for sharing this info @Chris. This is really huge.
 
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Chris

Chris

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I wonder if they can do something about the 0.69 OD in the 42RLE.
No, because that would requite rebuilding the transmission and addressing the mechanical parts themselves.

But, with the right gearing, it's more livable. My 5.38 gears aren't perfect, but they make it so much more tolerable than before.
 
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psrivats

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No, because that would requite rebuilding the transmission and addressing the mechanical parts themselves.

But, with the right gearing, it's more livable. My 5.38 gears aren't perfect, but they make it so much more tolerable than before.
Ah well.

I'm getting my Jeep regeared in 2 weeks btw. Decided that I'm going to stick to metric 32s and therefore going to 4.88s after talking to Dave.
 
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Chris

Chris

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Ah well.

I'm getting my Jeep regeared in 2 weeks btw. Decided that I'm going to stick to metric 32s and therefore going to 4.88s after talking to Dave.
You'll be happy. Anything is better than the stock gears.

Of course you'll have to swap them out again when you go to 35s... but don't worry, I won't tell anyone ;)
 
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zebra12

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Ah well.

I'm getting my Jeep regeared in 2 weeks btw. Decided that I'm going to stick to metric 32s and therefore going to 4.88s after talking to Dave.
I'm looking forward to your thoughts on the 4.88s. I have the same tranny and tire size as you (but I'll probably go up to 285s).
 
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Chris

Chris

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I want to add to this thread.

I spoke with Dave who owns B&G Performance today for about an hour on the phone. Super nice guy, very friendly, and told me quite a bit of information. Dave worked for Chrysler in the 90s and early 2000s and was one of the original software engineers for the TJ and various other Chrysler powered vehicles.

Because of this, Dave has a wealth of knowledge about these PCMs and how to access them. According to him (and I believe this), he is very well one of the only people in the world who can fully access the PCM on 97-06 TJs (he said he can do it all the way up to 2019 as well though) and have 100% control over them.

Some of the things he mentioned he could do to the PCM are as follows:
  • Activate / deactivate SKIM
  • Disable post-cat O2 sensors (allowing for cat removal without check engine lights)
  • Disable evap system (allowing for evap system removal without check engine lights)
  • Disable purge valve (allowing for removal without check engine lights)
  • Disable any other emissions
  • Change the temperature your cooling fan comes on at
  • Fully tune the air / fuel / timing curves
  • Change the VIN assigned to a PCM (so you can use it on another vehicle)
  • Enable / disable the automatic transmission module on 05-06 PCMs (so you can for instance, use a PCM from a 2005 manual transmission TJ on a 2005 automatic transmission TJ)
The list goes on, but that's just some of what he can do.

He mentioned he can actually tune the PCM even on a stock TJ so that you'll get a bit more performance out of it, and so it will run even better.

You can send him your PCM using this form and he'll tune it (and enable / disable any features you want) for $399, or you can buy the software from him for $599 and do it yourself.

The bottom line is that these PCMs are 100% tunable, we can just blame the misinformation that's been spread on the internet for making us believe that it wasn't possible. I'm very, very glad I looked into this further and decided to spend some of my time pursuing a solution to what many considered to be impossible.

This is actually a breakthrough if you ask me. It will allow TJ owners to keep their vehicles on the road for that much longer, but also tune them the way they want. No need for things like Split Second fuel controllers if you want to run boost, you can just tune the PCM directly and be done with it.

I encourage anyone and everyone to share this information and use B&G Performance for all your needs.

You no longer have to believe the lie that our PCMs are not accessible.