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Unread 01-02-2008, 04:34 PM   #16
RCHavok797
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I've seen on other drive by wire cars that people are putting a ground wire to the throttle body for better response. My friend did this on his Mazda 3 with good results.

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Unread 01-03-2008, 04:57 AM   #17
HurriJeff
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Yea... I kinda figure its a computer thing. Just kinda crappy, and funny too cause that fx45 thinks he's got you for that first 3 seconds then.. whammo.. see ya ! hehehe.

In all seriousness.. (snicker) its probably a good thing, in the big picture, its probably making a quiet difference in the WK overall safety rating, helping reduce certain types of accidents. Maybe people who inherently tap the pedal instead of easing it down. Probably benefits in snow and in low traction situations like boat ramp.
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Unread 01-03-2008, 10:29 AM   #18
2007GC Overland
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Hi Folks
My Hemi does not appear to have a hesitation problem - not that I can tell. It is my wife's jeep but on weekends I drive it. I looked to see if I could feel any hesitation this weekend or sense any - none. It responded to the push of the pedal. I normal drive a 6 speed Manual trany, V8 (LT1) Camaro - no hesitation there at all - so that is how I judge the Jeep.
thanks - just my 2 cents
Bill
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Unread 01-03-2008, 01:19 PM   #19
drewman141
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Bill - I believe what we are talking about here is not a hesitation like there is no movement or a delayed response to the pedal push. It is more of a hesitation of the full power of the engine when you drop the hammer. I'm sure in your camaro as in any RWD vehicle I've driven, when you drop the hammer those rear wheels are screaming. In the WK that does not happen, it kind of gently eases up and then bam you feel it blast through the power band. It is deffinately a different experience.
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Unread 01-04-2008, 03:50 AM   #20
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Quote:
Originally Posted by drewman141
Bill - I believe what we are talking about here is not a hesitation like there is no movement or a delayed response to the pedal push. It is more of a hesitation of the full power of the engine when you drop the hammer. I'm sure in your camaro as in any RWD vehicle I've driven, when you drop the hammer those rear wheels are screaming. In the WK that does not happen, it kind of gently eases up and then bam you feel it blast through the power band. It is deffinately a different experience.
It's just torque management. GM does it too with the supercharged Grand Prixs, only it's not as bad as what you guys are describing.
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Unread 01-04-2008, 05:57 AM   #21
2007GC Overland
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Quote:
Originally Posted by drewman141
Bill - I believe what we are talking about here is not a hesitation like there is no movement or a delayed response to the pedal push. It is more of a hesitation of the full power of the engine when you drop the hammer. I'm sure in your camaro as in any RWD vehicle I've driven, when you drop the hammer those rear wheels are screaming. In the WK that does not happen, it kind of gently eases up and then bam you feel it blast through the power band. It is deffinately a different experience.
Hi Drewman141
I have put down the hammer on my Jeep - it responded quickly but I noticed as the RPMs build up the Jeep pulled harder. I contributed that to the cam and the tuning. My 02 Camaro SS (Modified) does not start pulling hard until it hits 3500 RPMs (Cam), after 3500 hang on to the seats because it pushes you back hard. The Jeep appears to do the same. I will try it this weekend.
thanks
Bill
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Unread 01-04-2008, 06:17 AM   #22
anerbe
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The hemi engine seems to develop more torque in the higher RPMs, but there is a slight delay in full power in the low revs. I assume it's to avoid sudden shock to the driveline, especially in low traction situations where the vehicle may send all power from 1st gear to one wheel with full traction.

this could potentially be damanging to the car.
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Unread 01-07-2008, 11:38 AM   #23
2007GC Overland
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Hi Folks
Took the Hemi for a fun drive, turned off the traction control, and put the pedal to the metal - The Hemi has a power band ~2500 RPM to 5500 RPM, below that is pulling but not as hard as above 3000. This normal type performance profile I expected to see You might be able to tune the low end to pull harder but I have to believe the cam is setup for the power range above 2500 RPMs. You are pushing a 4700 vehicle, not include driver or passenger. I think it pulled pretty well for a vehicle its size.
Thanks
Bill
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Unread 01-07-2008, 08:15 PM   #24
falcon10
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I read in another forum sorry did not grab the link that many hemi owners figured out a way to recalibrate the throttle.

What you need to do is turn the key to on but do not start the car. when all chimes go away add pressure to the gas pedal til it is to the floor. Then release and turn key to off. Should at the next start raise rpms to 800 or so and heard that it will improve the hesitation some.

Many hemi owners seem to have done this and it has worked for the majority adding improvement.

Let me know how it goes
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Unread 01-10-2008, 06:27 PM   #25
JCDubya
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Quote:
Originally Posted by drewman141
Bill - I believe what we are talking about here is not a hesitation like there is no movement or a delayed response to the pedal push. It is more of a hesitation of the full power of the engine when you drop the hammer. I'm sure in your camaro as in any RWD vehicle I've driven, when you drop the hammer those rear wheels are screaming. In the WK that does not happen, it kind of gently eases up and then bam you feel it blast through the power band. It is deffinately a different experience.
What I experience is exactly that (the bolded portion ^). From a stop, you push the pedal then a second later you move. It's not a gradual build-up, it's an off-then-on sort of thing.
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Unread 01-11-2008, 04:28 AM   #26
HurriJeff
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Yes JC.. I get that too. I used to have a big carburated engine in a street rod and I used to "hop speed bumps" by taping the accelerator at just the right time. By preloading the front suspension then hitting the gas I could get the car to hop over speed bumps but it required about three perfectly timed taps and the throttle response had to be right now. Of course the WK is not about that in any way shape or form, but the experience of doing that had made me aware of throttle response. This Hemi has plenty of that "Drive by wire" lag between pedal push and tachometer move. By compairison.
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Unread 01-11-2008, 05:58 AM   #27
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Just dropped my kid off at school and I tested it. I can push the accelerator pedal all the way to the floor without feeling a surge if I do it quickly. It really does not compromise the driving satisfaction I get from my WK but it exists. There is a delay between pedal push and engine speed increase.
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Unread 01-11-2008, 06:51 PM   #28
JCDubya
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yeah, no doubt the HEMI is a fun Jeep to drive I just wish they could've addressed this issue as it would be a simple fix.

Once you drive it a for while you do get use to it but when i use my WJ THEN drive the WK I'm like, this sucks!

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Unread 01-24-2008, 05:10 PM   #29
fnckr
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My 2005 had a re-flash from the dealer and the problem no longer exists.

To be sure, from a stop, my Hemi would not respond to the first 1/4 of smooth throttle input and then lurch forward seemingly making up for it's inattentiveness. It was very hard to accelerate authoratively and smoothly. I could be a granny or a punk but no where in between.

After the flash the acceleration and smoothness correspond naturally with the throttle input.

The flash is referred to in one of the TSBs. If I find it I'll post. It might be on the WKJeeps.com site.
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Unread 01-24-2008, 11:52 PM   #30
AZCoronaDog
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My 2008, purchased on 12/22/08 does not seem to have this issue.
My daily driver is a 2002 Camaro SS, so I do know what good acceleration is all about (13.3 @ 106 in the 1/4).

I read this thread awhile back, but I didn't want to post until I was sure I had thoroughly tested for this problem.
I tried light power braking as a comparison to just hammering it, and there was very little difference, so I'm satisfied that the Jeep accelerates just fine.

Update: I punched it off the line the other day and got a nice little chirp from the front tires (Quadra Drive II full time 4x4). I was able to repeat this at the next light too, so apparently the throttle delay can be fixed (at least on the '08).

Last edited by AZCoronaDog; 02-03-2008 at 12:38 PM..
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