I know this is going to sound crazy but. This weekend I was cleaning my truck inside and out, which meant the doors were open quite alot. Well after I was done I jumped in to pull it out of the driveway and it barely started, I turned it off tried again and no start. Battery completely dead. Jumped it and drove it strait to the dealer, they replaced the battery. Then I remember when I originally picked it up the salesman took awhile to get back and said that he had to charge the battery because it was dead. Anyway Ive been driving it all weekend and today and the rough idle I use to have while stopped at a light IS GONE. Dont know how or why but man is it nice.

P.S. Yes I had tried dissconnecting the Battery before to reset the Idle but it never worked.

 

You suppose they reflashed your truck while they had it?
Or do you think it's just changing the battery (thus implying you had a bad battery all along)?
Chris

 

They did check for a newer reflash but I allready had the latest from back in December. My guess is the battery was bad all along. But could this really make a difference? I dont know, but like I said it sure is sweet.

 

There is a TSB for rough idle, my dealer is jerking me around saying its up to date, but with a build date of 2-14-04 i doubt it

 

My build date 11/03 and I had a reflash on 12/14/04. The tech took me back and showed me with his computer hooked up to my truck that that flash was the latest. It had all but totaly eliminated the throtle lag and most of the rough idle but not all. But since the new battery she idles smooth as silk. I dont get it but im not going argue with it. Just wish I knew why.

 

I have never thought about it but for what its worth....I went to crank my 97 Ram SS/T one morning and it would crank and fire up fine but would not idle at all. You could keep reving it up and it would run but as soon as you tried to let it idle it would die. The truck was out of warrenty so I called the Dodge dealer and asked to speak to a mechanic I knew there. He told me that I needed a new battery...I didn't see how it would be the battery since it cranked fine, but sure enough I put a new battery in and it worked fine. Since then my sisters 96 Cougar and my mom's 99 Expedition did nearly the exact same thing (except the would idle just very roughly)....a new battery fixed both of them! I was told its because the PCM requires a certain consistant voltage and if it doesnt get it it will not operate correctly.

So its very possible the new battery did fix the rough idle you had!

 

I had the exact same thing happen to a 97 Dodge Dakota, and it was fairly new at the time. It would barely run, new battery and boom.... fixed.

 

That's some wierd chit. I had a bad battery but never noticed the rough idle... now on my second battery I've noticed lately it just doesn't purrr like it used to. Wonder if this battery is worthless? Might be time to just go get a Optima and screw this OEM-JCI built crap!

 

Thats what I did D, put a red top in and it damn near rips the motor mounts spinning it over!

 

I notice they carry Optima Red and Blue at Costco. They ain't cheap. I think I would just buy the best 'normal' battery they have that fits. It would be fine, and about half or less of the price.
Chris

 

it might be a dodge thing, i had a durango and it did the same exact thing, cranked fine then it died if i wasnt reving the engine. as far as the rough idle goes i might have to try that because im running pretty rough right now.