Feels like im in "Limp" mode.....

A couple of issies i have noticed lately have me thinking. First is the feel of lack of power. Seems like i have to almost mash the skinny pedal jist to get the fat box up to speed. I never had to do that before and i thought it had something to do with the spare being on for a couple of weeks. Now i have a new tire and it has not changed. I dont have any dummy lights or codes popping up so im lost. Looking for possibilities here.

Second, the cruise control seems to be "hunting" to keep up the preset speed. I know its supposd to do that when going up or down a mountain/hill, but on a flat road and minor overpasses? C'mon now, my Jetta hardly/never changed gears when on cruise. Can it have someyhing to do with the larger wheels? If so, what would be the fix, tranny flash?

My XK felt a little sluggish today for some reason. Not exactly sure why.

It's hard to diagnose something that isn't broken. All kinds of stuff can cause sluggish performance bro. You put tons of miles on those tires you should be use to the change by now.

yeah if you just put the tires on, that's one thing..... but for it to all the sudden feel sluggish out of nowhere is kind of odd.

Did the shifting in OD just start too? If not, stop trying to compare it to your Jetta. Our commanders are the aerodynamic equivalent of a piano... the slightest change in head wind will cause it to down shift on the highway, especially the 3.7L which is already at its limit of the size of vehicle it should be pushing (let alone a lifted one with larger tires).

Thats what is odd. It drove fine throughout my trip (except) the cruise control thing. But here at home, it just doesnt feel right. I know its a brick box and the weight of the wheels/tires doesnt help, but something is not right. Do you think that the altitude change of the trip confused (for lack of a better word) the computer? Therefor not feeding the right amount of fuel to air mix or something.....? Pulling at straws here.

Matt, the shifting issue is not in OD, its in cruise control.

I think Matt meant was are talking about the trans going in and out of OD while the cruise on. You might have just got some bad gas maybe that would cause sudden sluggish performance.

It would downshift and a couple of seconds later downshift again for higher revs. Once it got to the set speed it would upshift back into OD. It is doing it way too often like the shift curve is off or something.

I did have a hell of a time on the highway of Western NC and NW Georgia. I think on one uphill it was pulling 6g at 45mph and was strugling at that. I believe we were around 3500ish feet above sea level there vs 0 here.

I hope it is bad gas. I guess i will have to wait till the next fill up.

The hilly, mountain terrain up here is a lot different from what you see down there in Fla. I run cruise on the interstate and it is normally fine, when it gets to a hill it downshifts but yet it keeps its speed. When Im on a road like Rt 29 which is a 4 lane highway but yet it is nothing but hills, one after the other, I dont run cruise because it is constantly downshifting , sometimes all the way to 3rd. If youre not use to running cruise in the hills then you may think there is a problem. How was the gas mileags during your trip ? One year on the way back from the Outer Banks I had to stop to gas up. I should be able to make that trip easily on a tank of gas. I think I just got some bad gas. The jeep had a hard time keeping up to speed and felt sluggish. The temp outside was 107 degrees too so I dont know if that was a factor also.

I was going to say you could check the trans fluid.... but you don't have a dipstick...

The computer does a pretty good job of adjusting for altitude so that shouldn't be an issue. Do you have a scanner you can hook up to read some data? Would be a good idea to check things like the coolant temp sensor, air intake temp sensor, manifold pressure and 02 sensor readings to see if something is off.

I'd run threw that tank and see what happens maybe just for ****s and giggles reset the computer and see what happens.

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Originally Posted by Sal-XK

I'd run threw that tank and see what happens maybe just for ****s and giggles reset the computer and see what happens.

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I was thinking of reseting the comp,..... how long do i wait before reconnecting the battery?

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Originally Posted by NeilSmith

The hilly, mountain terrain up here is a lot different from what you see down there in Fla. I run cruise on the interstate and it is normally fine, when it gets to a hill it downshifts but yet it keeps its speed. When Im on a road like Rt 29 which is a 4 lane highway but yet it is nothing but hills, one after the other, I dont run cruise because it is constantly downshifting , sometimes all the way to 3rd. If youre not use to running cruise in the hills then you may think there is a problem. How was the gas mileags during your trip ? One year on the way back from the Outer Banks I had to stop to gas up. I should be able to make that trip easily on a tank of gas. I think I just got some bad gas. The jeep had a hard time keeping up to speed and felt sluggish. The temp outside was 107 degrees too so I dont know if that was a factor also.

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The gas milage was a bit lower because of the hills but not by much. Im getting crap milage anyways (12mpg highway...wtf), so idk. When i was off of cruise i could hold a set speed by applying little gas and it didnt diwnshift but git up to speed. Same scenario with cruise control on and the pedal would drop and double down shift, which really wasnt necessary.

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Originally Posted by Matt_

I was going to say you could check the trans fluid.... but you don't have a dipstick...

The computer does a pretty good job of adjusting for altitude so that shouldn't be an issue. Do you have a scanner you can hook up to read some data? Would be a good idea to check things like the coolant temp sensor, air intake temp sensor, manifold pressure and 02 sensor readings to see if something is off.

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No i dont, but know someone who does. I need to change the trans fluid anyways because i overheated it a couple of times at Uhwarrie.

12MPG highway with a 3.7L sounds really wrong bro and with the tires not being corrected it's really around 13MPG which is still bad. Something is wrong and you need to start considering your maintenance. How long since the diff, TC and Trans had been serviced. How about plugs filters wires oil and things like that.

Not since ive had it, maybe a year? I know its time, should i use Royal Purple?

I think that's personnel preffrence its a top brand you can't go wrong with it. I used Mobile 1 on the last change and it seems to working out pretty good I know a lot of people use royal amsoil and mobile 1 seem to be the top three.

I'm a big advocate for AMSOIL. I used to use RP but liked the ordering method through AMSOIL and they're very specific with their applications and documentation. Mobile is also good.... but I just don't like giving Exxon/Mobil my money, they're rich enough.

Ok, so i will look into those three and change all the fluids. Im sure if i search i can find my answer but im feeling very lazy....what plugs should i use?

Champion Coppers! Don't get anything fancy for the plugs.

matt is right (mopar) champion copper plugs ONLY every 30k miles.i have worked on dozens of newer jeeps and there really picky when it comes to plugs weather there worn out or a diffrent brand (like bosch platinum 2's they really don't like those),and atf+4 in the trans every 30k miles also.engine oil brand shouldn't matter as long as your using the right viscosity changing when you should and not using wallmart supertech oil lol. clean the throttle body also, old rag/tooth brush and small amount of carb cleaner it WILL make a diffrence.i have done all that and with 265/70/17's and a 3.7 still get 21mpg highway, 15 to 17 city.

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Originally Posted by chevelleman4292

matt is right (mopar) champion copper plugs ONLY every 30k miles.i have worked on dozens of newer jeeps and there really picky when it comes to plugs weather there worn out or a diffrent brand (like bosch platinum 2's they really don't like those),and atf+4 in the trans every 30k miles also.engine oil brand shouldn't matter as long as your using the right viscosity changing when you should and not using wallmart supertech oil lol. clean the throttle body also, old rag/tooth brush and small amount of carb cleaner it WILL make a diffrence.i have done all that and with 265/70/17's and a 3.7 still get 21mpg highway, 15 to 17 city.

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I'm lucky to get 15, it's more like 13.5 average. I guess I should update this thread by saying that the "limp" feeling I was getting was caused (my guess) by crappy fuel. I have since stopped going to that gas station and have not felt the Jeep to be sluggish, it's not a race car but at least it feels like when I first drove it. I still have to replace the plugs and fluids, so I will report back on my findings after that happens.

Champion spark plugs and Jeep have a long history together. Both were manufactured in Toledo.
I say Champs.

Your rack on top can reduce your MPG. Have you tested it straight hiway driving?

Tire sizes also affect your MPG.

Caleb, did you see my story about when my cruise stopped working?

I replaced my plugs last year and it made quite a difference. They were worn pretty bad and the tips were dissapearing. It made a huge power/throttle response/acceleration difference with the new plugs in it. I don't remember which plugs i got. I think they were bosch plats. They seem to work fine. I also like the copper plugs. They are usually the best performing plugs all around. In some cases however (my VW GLI) it will chew through the coppers in about 3500 miles. I have to go with irids which is what the car comes with.

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Originally Posted by cico7

Champion spark plugs and Jeep have a long history together. Both were manufactured in Toledo.
I say Champs.

Your rack on top can reduce your MPG. Have you tested it straight hiway driving?

Tire sizes also affect your MPG.

Caleb, did you see my story about when my cruise stopped working?

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The rack and tires did drop my mpg, but I started with only 14.5 or so.

I missed your cruise control issue.....gotta link?