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new hemi hesitation?

Posted By: 68LAR

new hemi hesitation? - 03/15/12 03:27 AM

My new truck has a 5.7 Hemi. Great truck with only 2700 miles on it. The only issue I have is an off idle flat spot or hesitation. It's very noticable when leaving from a dead stop and "nailing it". The engine will just sit there for what seems like a full second or two then take off. Is this normal, or is there some "fix" for it?
Thanks for any help.
Posted By: 72swgnr

Re: new hemi hesitation? - 03/15/12 03:29 AM

I've had the same issue on my 2011 Charger RT and believe it has to do with the electronic throttle control. Not sure if there is a fix for it or not. Also had the hesitation on my 09 hemi ram
Posted By: SNK-EYZ

Re: new hemi hesitation? - 03/15/12 05:28 AM

I can't say if it applies to your truck (you didn't post the year) but it may help.

From www.chargerforums.com
http://www.chargerforums.com/forums/showthread.php?t=8118


2006 Dodge Charger
Reset & Calibration Procedures


Throttle Calibration

Throttle calibration can substantially improve throttle responsiveness over "factory standard." Many people notice what appears to be sluggish throttle response or a "dead area" at initial accelerator depression. Throttle calibration can take care of these.
1) Insert ignition key and turn to "ON" (not start).
2) Wait for all idiot lights to go out. Check Engine Light may remain on.
3) Slowly depress the accelerator pedal all the way to the floor.
4) Slowly release the accelerator pedal until it's all the way back up.
5) Turn the ignition key to "OFF".
6) Start the engine.
Most drivers notice an immediate change in throttle response, but depending on your driving style, you may need to repeat this procedure periodically due to the computer's adaptive programming. You likely need to repeat this procedure any time the battery is disconnected.
Posted By: 68LAR

Re: new hemi hesitation? - 03/15/12 01:55 PM

Quote:

I can't say if it applies to your truck (you didn't post the year) but it may help.





It's a 2011. I'll try resetting the gas pedal today. I can't see it hurting anything.
Thanks
Posted By: ZIPPY

Re: new hemi hesitation? - 03/15/12 03:40 PM

Quote:

1) Insert ignition key and turn to "ON" (not start).
2) Wait for all idiot lights to go out. Check Engine Light may remain on.
3) Slowly depress the accelerator pedal all the way to the floor.
4) Slowly release the accelerator pedal until it's all the way back up.
5) Turn the ignition key to "OFF".
6) Start the engine.






7) Congradulations, you have successfully reset your
oil change reminder light



I'm sorry to be an internet mythbuster but there is no such thing as a do-it-yourself throttle calibration.

There is however such a thing as "throttle relearn", but it's only needed when the throttle body is swapped out and it requires dealership quality scan tools to perform. But it also has no effect at all on throttle response.

Here is how to reduce electronic throttle lag:

With no money invested-
1.Battery disconnect. 30-60 minutes is good, if you have the time.
2.Reconnect the battery, fire it up and drive it like an absolute maniac. Give it all the WOT you possibly can, as long as you possibly can.
(A dragstrip is probably best for obvious safety reasons)

Not only will the throttle response improve, but the trans shift quality will improve. This is due to the adaptive memory in modern vehicle pcms; If you drive it very easy for very long, the vehicle will learn your driving habits....the throttle will act slow and the trans will shift like oatmeal. If you drive like a maniac long enough, throttle response 'wakes up', the trans shifts harder, and it will feel better to a performance driver.

But, the effect is temporary. Drive it really slow and easy for 3 trips of 50 miles or more, adaptive memory will take over and it will go back to the way it was.

For a more long lasting improvement, put a 77070023 cold air intake on it. Throttle response gets better in all kinds of driving, and I have seen a 25HP gain at the rear wheels with just that one part change, above 5000rpm. I know alot of people say cold air intakes don't work, but that particular one is actually good.
Posted By: Savoy1964

Re: new hemi hesitation? - 03/15/12 04:24 PM

I cured my hesitation on the challenger by upgrading the Throttle Body to the next bigger and cnc'ed one. After 10 minute install ran much better.
Posted By: Cheatham

Re: new hemi hesitation? - 03/15/12 04:44 PM

Try looking or asking at Ramforumz.com lots of good info on Ram trucks
Posted By: AlexP

Re: new hemi hesitation? - 03/15/12 05:47 PM

I used to have really good luck with putting the parking brake on, putting it in drive and letting it sit and idle in gear (while sitting in it). Sit for about 15 mins.

This cured a lot of idle and throttle issues with modified hemi's.
Posted By: 68LAR

Re: new hemi hesitation? - 03/15/12 05:59 PM

Quote:

Quote:
--------------------------------------------------------------------------------

1) Insert ignition key and turn to "ON" (not start).
2) Wait for all idiot lights to go out. Check Engine Light may remain on.
3) Slowly depress the accelerator pedal all the way to the floor.
4) Slowly release the accelerator pedal until it's all the way back up.
5) Turn the ignition key to "OFF".
6) Start the engine.



--------------------------------------------------------------------------------




7) Congradulations, you have successfully reset your
oil change reminder light






Thanks, that's too funny.
If the computer is "self learning", wouldn't the same thing happen in reverse? I mean, instead of driving it normally, start beating on it. Should the throttle response and shifting improve???
I'm just asking, I'm too old to understand this new technology.
Thanks for the help.
Posted By: ZIPPY

Re: new hemi hesitation? - 03/15/12 07:23 PM

Quote:


Thanks, that's too funny.
If the computer is "self learning", wouldn't the same thing happen in reverse? I mean, instead of driving it normally, start beating on it. Should the throttle response and shifting improve???
I'm just asking, I'm too old to understand this new technology.
Thanks for the help.




Glad you saw the humor in that

Yes, if you just beat on it more while driving it, it should come around a certain amount...but it does take a little while for the pcm to learn your driving habits have suddenly changed.

I mentioned battery disconnect because that's the easiest way to clear some of the adaptive memory, and the results are much more immediate.
Posted By: Jeff_383

Re: new hemi hesitation? - 03/15/12 11:32 PM

Can you just get it tuned out like on GM vehicles?
Posted By: 72swgnr

Re: new hemi hesitation? - 03/15/12 11:48 PM

Quote:

Can you just get it tuned out like on GM vehicles?




Chrysler decided to use top secret computers on the 2011 and up vehicles. So far no one has been able to crack the codes in the aftermarket industry.
Posted By: Turbo392

Re: new hemi hesitation? - 03/16/12 12:50 AM

I can punch it to the floor and release quickly without the throttle even cracking open, but with a scanner showing the pedal sensor working. It's a Dodge thing.
Posted By: keefe

Re: new hemi hesitation? - 03/17/12 10:20 PM




For a more long lasting improvement, put a 77070023 cold air intake on it. Throttle response gets better in all kinds of driving, and I have seen a 25HP gain at the rear wheels with just that one part change, above 5000rpm. I know alot of people say cold air intakes don't work, but that particular one is actually good.




Zippy.. Does the 77070023 cold air intake work on a 2005 hemi ram also ?
Posted By: ZIPPY

Re: new hemi hesitation? - 03/18/12 01:56 AM

Unfortunately no, that part number will only fit 2009 to '12.

For 2003-2005 the engine and body/underhood sheetmetal are different, so there is a different cold air intake for that truck....it is 77060005AB. It does help the throttle response noticeably, but it does not have the HP gain the later model cai has. If I remember the old tests correctly it picked up about 12hp.

However!! an '03-'08 has an option available that the newer truck does not have: an SRT-10 hood swap, an open hood scoop, and an air duct that attaches underneath the scoop to route the air to the cai box. I tried all that stuff on my 2003, and even with over 200,000 miles on the truck it did make a noticeable difference. Plus I think it looks cool

LMK if that is of any interest, I'll round up all the PNs for ya if you need them.

Attached picture 7123522-DSC00670.JPG
Posted By: ZIPPY

Re: new hemi hesitation? - 03/18/12 01:57 AM

airbox/air duct/whatever the heck it is called

Attached picture 7123529-DSC00669.JPG
Posted By: ZIPPY

Re: new hemi hesitation? - 03/18/12 01:59 AM

The scoop (with a fancy insert, found it on ebay, the stocker is black plastic)

Attached picture 7123531-DSC00666.JPG
Posted By: keefe

Re: new hemi hesitation? - 03/20/12 12:08 AM

Thanks Zippy, That looks great on your truck. My truck is a 05 daytona so I think the hood is the same. When you get chance can you Pm me the part numbers, no rush this is a down the road project for me.. lol
Thanks Keefe
Posted By: 1badx

Re: new hemi hesitation? - 03/21/12 07:17 PM

Quote:

My new truck has a 5.7 Hemi. Great truck with only 2700 miles on it. The only issue I have is an off idle flat spot or hesitation. It's very noticable when leaving from a dead stop and "nailing it". The engine will just sit there for what seems like a full second or two then take off. Is this normal, or is there some "fix" for it?
Thanks for any help.




What year is the truck? You mention new and I'm assuming 2011 or newer but..... if it's a 2010 or older email me.
With the purchase of a tuner (Predator or Trinity) we can take care of that hesitation and get you some better mileage
Posted By: 68LAR

Re: new hemi hesitation? - 03/22/12 04:29 PM

As I stated in my second response, it's a 2011. From all the info I have gathered, there doesn't seem to be a cure for the 2011 hesitation just yet.
It is supposed to be a self teaching computer. Any adjustment made to the computer will be short lived, supposedly..... I don't race the truck, so it's not that big a deal at this time. If I "lay" into the gas, it flat a.. hauls.
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