Does anyone run a tune on their TJ?

73Elkheartgreen

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Has anyone here had any luck with using a tuner? My 2004 TJ has about 145000 miles and while it seems to have good power, it seems to fall off rather quickly on even small hills. Is this something any of you would recommend or stay away from?
 
Has anyone here had any luck with using a tuner? My 2004 TJ has about 145000 miles and while it seems to have good power, it seems to fall off rather quickly on even small hills. Is this something any of you would recommend or stay away from?
Which engine do you have?
 
Which engine do you have?
He put the 4.0 in the profile, so we can go off that for now.
... it seems to have good power, it seems to fall off rather quickly on even small hills.
I’m not understanding what folks are expecting from a straight six with less than 200 engine hp and oversize tires?!

edit; I’ll even take the oversize tires out of the equation. It’s a Jeep.
 
@Chris has a tune on his from Flyin Ryan Performance and says it has helped with how his TJ runs. He would be the best person to comment on this.
And Ryan is a member and talked about this a while ago.
 
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What is the difference between a tune and a performance chip? How is a tune installed?

All of the tuning I've had done is loaded directly on the Jeep ECU. (that said, none of my tuning specifics are going to be relevant to this discussion so I'll leave it at that.)
 
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You can give your Jeep a tune-up but there are no tunes that will make any difference. If you want power you need a different rig. The 4.0, 2.4 and 2.5 are not capable of any real power by modern standards no matter what the tune.
 
You can give your Jeep a tune-up but there are no tunes that will make any difference. If you want power you need a different rig. The 4.0, 2.4 and 2.5 are not capable of any real power by modern standards no matter what the tune.
Why is that? Most all other modern engines have room to improve except the 2.5 and 4.0?
 
What is the difference between a tune and a performance chip? How is a tune installed?

I'll try to answer this with my limited knowledge about some of this stuff.

A CHIP if I am understanding what you are asking about is some thing you place inline with the PCM. I think Jet Performance use to offer one such item for the TJ.

What I have always been told about performance chips were that would change the way the engine would run for a short time and then the stock PCM would compensate for the performance chip and it would go back to running like stock.
The whys of this I don't fully understand other than the stock PCM won't allow it.

With a TUNE it is installed into the PCM to replace the stock tune which then has new parameters for the engine to operate with.
By changing the parameters you can gain some performance improvements. It isn't anything like the diesel world is able to but yes there is some that can be gained.

To notice more performance gains you have to do modifications to the engine also. And I am talking about internal modifications along with external mods.
Examples are cams with a more aggressive profile, higher compression pistons, cylinder heads that offer more air flow.
Then other things like larger throttle bodies, larger injectors that flow more fuel, exhaust headers, larger diameter exhaust & free flowing mufflers & catalytic converter. All these things have to be paired together to work properly. It's no difference than the same principles that old Hot Rod people applied over the years. Now you just have to make the electronics work with these modifications.

You can give your Jeep a tune-up but there are no tunes that will make any difference. If you want power you need a different rig. The 4.0, 2.4 and 2.5 are not capable of any real power by modern standards no matter what the tune.

I would say this isn't correct per Chris & his experiance with the tune he has been running on his TJ.

And I can say that I was able to notice a difference in how my TJ ran with my V-8 and have talked to other people with the Dodge V-8's who were able to notice gains even with their stock engines and no other modifications done.
Are we talking about the type of gains that the diesel crowd is able to get? Heck no but there are dyno runs where people have picked up 25-50HP from fairly stock engines. I'm talking about the V-8 not the 4.0 or 2.5/2.4. I do not know what you can gain on those engines.
 
Why is that? Most all other modern engines have room to improve except the 2.5 and 4.0?
Aren't the TJ 4.0s just an updated AMC I6 from the 70s? So a 25 year old design when the first TJ rolled off the line and a 32 year old design by the time the last ones rolled off the line.

My assumption (that may be very wrong) has always been that Jeep kept increasing performance of this engine over the years and got about as much as they could out of it (and sizable gains too). Now, if you go outside of the boundaries that Jeep had (mpg, emissions, lifespan, etc) I suppose you might be able to eek out a little more power.
 
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You can buy trucks today with over 500hp, tweaking our Jeeps so they can keep up with a 10 year old Toyota Camry is stupid.

I guess I ain't trying to tweak my TJ to keep up with a Camry I'm just trying to make it run better and if a little more performance happens then that is a good thing.

You can get tunes that are a similar to stock just improve upon the stock parameters.
Then a 89 octane tune for a little more performance
Then a 91 octane tune for a little little more performance

Will any of these impress many from the tuner crowd? Nope but again Chris has said that he's noticed a difference so I'll take his word for it. This is just like any other modification we do to our Jeeps. For some they choose to do this and are happy with it. For others they have no use and see no need for it.

This is what makes thigs great isn't it?
 
I'll add a little to what @Wildman said. The "chips" that were produced for primarily 4.0 l jeeps were little more than what I call foolers. They don't actually change the base program in the ECU. They simply override the program. A "Tuner" reprograms the ECU to allow for custom air/fuel mapping, timing curve, spark duration, etc...
A 'custom tune" done by some one knowledgeable, especially when combined with a dyno, can be programed to exacting specifications that work best with what ever engine modifications you have.

A custom tune can be made to enhance how a vehicle runs specifically to how it is going to be used. Granted there are not HUGE gains to be had tuning a stock 4.0 but a cleaner running engine is a happy engine..
 
Put your money where you feel there is value. In 4LO I never want for power and for me that's all that matters. As far as tuning for higher octane gas, not a chance. I really enjoy buying the cheap stuff. Seems like @reddvltj and @Wildman don't have a tune either so I guess they don't think it's worth a damn either.
 
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Put your money where you feel there is value. In 4LO I never want for power and for me that's all that matters. As far as tuning for higher octane gas, not a chance. I really enjoy buying the cheap stuff. Seems like @reddvltj and @Wildman don't have a tune either so I guess they don't think it's worth a damn either.
Now you're just making a fool of yourself putting your assumptions out there trying to represent me and my thoughts on tuning. I haven't done anything with my Jeep for the simple fact that I have other priorities at the moment I do in fact have every intention of having my computer reprogrammed. When I am ready to and can financially afford it.
 
You can buy trucks today with over 500hp, tweaking our Jeeps so they can keep up with a 10 year old Toyota Camry is stupid.
So true. My brother bought a new Ford F-150 3.5 Ecoboost and tuned it. It's lifted on 35s too. That thing is a rocket compared to my Jeep. The tune added 125 hp and almost as much torque. It's putting out around 445 hp and 500 ft lbs of torque now. I'll never drive that thing again. :(
 
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I have a super chips trail dash tuner in my Jeep. I don’t know a whole lot about it, but here is what I do know. When I purchased the Jeep it was set to “fuel saver” (if I recall correctly) and the throttle was much more sensitive in every gear. It also felt as if it had more low end power, smash the gas and it was responsive (as responsive as a I6 gets). After some awful trail adventures I returned the tune to stock. The throttle is way less sensitive and I feel the Jeep is more sluggish than before. It’s also how I expected it to be and remember TJ’s driving from years ago, probably normal. I leave the trail dash attached, it had some nice options to view stats and let’s me read codes any time if needed.
 
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He put the 4.0 in the profile, so we can go off that for now.

I’m not understanding what folks are expecting from a straight six with less than 200 engine hp and oversize tires?!

edit; I’ll even take the oversize tires out of the equation. It’s a Jeep.
I am expecting to Fuck off the stupid pre cats and o2 sensors on my 06 eventually! having a 6 cylinder gas guzzling "Brick" with emission controls that are just "The Emperors New Cloths" Plus we dont Smog or MOT in Australia ( for our UK brethren) :) But I do want to ask about exhaust smell for those that have deleted their cats.
 
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