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daffydak
GenIII
7/15/2004
01:07:44
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 Subject: 4.7L hesitation/rough idle on cold start
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Message:
i just wanted to know if this is normal... when i first start my truck (00 cc 4x4 4.7L auto 49k on the odo) it sometimes idles a little rough, and has a pretty good hesitation from a stop(when engine is cold). if i barely give it gas, it dosent do it. but if i give it about 1/4 to 1/3 of the pedal, it hesitates for about 1 second... it runs great before and after the hesitation (except the sometimes rough cold idle) i recently cleaned the TB, adjusted my tps to .76V (again, the problem was there before this "mod") and changed the plugs (it did it with the other plugs it had as well) i have run fuel injector cleaner through it sevral times, to no avail...
it dosent do it when its been running for a little bit (it even hesitates when in park/neutral) I have learned to get over the low idle with the a/c off, but this kinda ticks me off! i'm not too worried, as the truck runs like a raped ape otherwise!
thank you for your time...
Dan
MOPAR=More Power!!
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idle
Dodge Dakota
JOIN HERE
7/15/2004
08:21:56
|  RE: 4.7L hesitation/rough idle on cold start
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I had the same problem. I had to get my pcm(i think it was the pcm?) flashed at my local dealership and that took care of it.
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daffydak
GenIII
7/15/2004
08:39:36
| RE: 4.7L hesitation/rough idle on cold start
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Message:
thanks,
i hope it dosent include the death flash! i noticed that even if i drive it about 1 block, the hesitation goes away! i guess its not that big a deal, i'm just critical of my truck :-) i'm still under warrenty, i guess i'll give the dealer a call..... (if the flash dosent pull any timing) maybe i can slip the tech an extra $20 to give me a few more degrees of timing advance :-P
Dan
MOPAR=More Power!!
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Kowalski
GenIII
7/15/2004
15:26:17
| RE: 4.7L hesitation/rough idle on cold start
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I'd be surprised if the tech was able to advance your timing, but wouldn't be surprised if he took your $20 anyways. Did you disassemble and clean the IAC while you were cleaning the TB ?
Lead, follow, or get out of the way
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daffydak
GenIII
7/16/2004
00:40:33
| RE: 4.7L hesitation/rough idle on cold start
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yep i cleaned the iac and its port thoroughly (and carefuly)
Speaking of the dealer.. do you think they would freak out on my modded tps??
thanks again.
Dan
MOPAR=More Power!!
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flash
Dodge Dakota
JOIN HERE
7/16/2004
01:06:39
| RE: 4.7L hesitation/rough idle on cold start
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Message:
There is, in fact a reflash that will probably cure your problem. I would say that it is not a "death flash" but I cannot say for sure. When these flashes are performed nobody knows what changes they actually do to your PCM, not even the techs. Only the engineers and programmers know for sure. Since there has been little or no spark knock complaints about the 4.7L, I doubt that any timing changes will be made. As a tech, I wish I could actually alter the timing myself, but I can't. I guess if it doesn't bother you and does not get worse and you don't want to risk a possible "death flash" don't worry about it. If it progressively gets worse, no flash will fix it and you have another problem and should have it looked at.
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daffydak
GenIII
7/16/2004
01:19:16
| RE: 4.7L hesitation/rough idle on cold start
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cool sounds like i will be calling the dealer monday! how long do you think it will take to flash my pcm? 30 mins at the most?? they should tell me, but I want to know ahead of time!
thanks everyone!
Dan
MOPAR=More Power!!
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Kowalski
GenIII
7/17/2004
07:56:08
| RE: 4.7L hesitation/rough idle on cold start
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Message:
One more thing to consider would be the condition of your spark plugs/air filter. If you're sure you've got all that stuff in good shape, and don't want to risk a flash that might retard your timing, you could bump your idle up a little. This is controled by a tamper resistant torx head screw adjusting the throttle blade stop. The correct tool should be availabe at parts stores, or you might do as I did - turn it by grabbing the exposed threads with needle nose pliers. This should only be tried once everything else mentioned here has been checked. You shouldn't have to adjust it much.
Lead, follow, or get out of the way
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daffydak
GenIII
7/17/2004
11:39:07
| RE: 4.7L hesitation/rough idle on cold start
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Message:
Yep good plugs and air filter (i changed them about 2K ago) the plugs are autolite 5224 copper, Napa gold air filter. I have alot of torx bits, I believe its T25. I adjusted the "base" idle on my 3.9L that way. I didn’t know you could do that on the 4.7L as well... the hesitation really REALLY irritates me! I guess its no big deal, since its fine within driving for a block or so... it just bugs the heck outta me =P i want my truck to run PERFECTLY! lol
Thanks!
Dan
MOPAR=More Power!!
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Dktasfugnrox
Dodge Dakota
JOIN HERE
7/17/2004
14:25:34
|  RE: 4.7L hesitation/rough idle on cold start
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New to the Dakota family... I just got a 4.7l V8 and I read somewhere before I bought it that since its a SOHC it take longer to get the oil and temp of the engine to where it should be. To assist with that they set the engine to stay in first gear longer to rev the engine up and not let you accelerate like it usually would. Is that what u are talking about or is it a different problem?
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Kowalski
GenIII
7/18/2004
07:12:59
| RE: 4.7L hesitation/rough idle on cold start
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Message:
That is not what is being discussed here at all. Where the cam is positioned in the motor really has nothing to do with how long it takes to warm up. You accelaerate quicker in lower gears so the rest of what you read sounds like nonsense too. Where are you reading this stuff ?
Lead, follow, or get out of the way
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nik
Dodge Dakota
JOIN HERE
3/25/2010
16:52:21
| RE: 4.7L hesitation/rough idle on cold start
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Message:
hello all. my mother in law has a 94 95 dakota with the v8. same problem. just wondering what i should check first before i go and spend ton$. first start and dies. give it gas to warm it up and it runs. low idle, around 1/2 1k on tack at all times warm or cold. and sometimes wants to die comming to a stop. any help? thanks in advance.
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daddio
Dodge Dakota
JOIN HERE
3/25/2010
17:16:41
| RE: 4.7L hesitation/rough idle on cold start
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Message:
Take the battery out and have it load tested. These symptoms are the first signs of a weak battery. The low battery will crank the motor but voltage goes low enough for the PCM to lose idle memory until the alternator brings the charge up.
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