Have developed a rough idle. Cause/Fix?

[Zed 71]

Is there a difference between the ambient temperatures when you experienced pinging versus no pinging? Since it is the season for cooler temperatures, the relatively denser air changes the air/fuel mixture which may reduce/eliminate pinging.

 

[nick1126]

Kirk, I need your help, this forum will not let me send you a message or an email

Sorry for being a pain in the ass. Im having the same problem as you had on another post, started out as if I wasn't releasing the gas while slowing to a stop but was manageable. Now its starting the bucking etc.


Someone suggested the idle air control valve which I have not tried.

Did you solve your problem? If so how?

BTW mine is a 2000 Limited 5.7 but seems to be the same problem.

Any help would be appreciated

Thanks
Ron
[email protected]

 

[OklaHemi]

my 07 has the same effin problem, there is a lot of talk in the dodge community about grounding your throttle body to reduce the "noise interference". i just held a wire from the throttle body to the engine block where the battery was grounded but it did not make a difference. i have tried just about everything and have had 2 dealerships tell me these engines run rough, that is absolute BS it did not run rough when i bought it and would never pay 30k+ for a vehicle that did. im a little pinched for time at the moment but i want to try a different grounding point other than the engine block since that is where i would think the interference is coming from.

 

[KMeloney]

Never heard anything about grounding-out the TB (or anything, for that matter), so keep us posted. Some more info about the theory here would be helpful, too. Thanks.

 

[OklaHemi]

here is a post from another forum

Basically you take a piece of wire, 12 gauge would probably be fine or anything thicker, and loosen one of the bolts holding the throttle body on (there are four, one in each corner on the face). Connect the other to chassis ground or the negative battery terminal and you're done. Five minutes if you have a CAI as the bolts are right there in front of you, 10-20 minutes if you have to either finagle a way around the "Hemi Hat" or remove it to get it out of the way.

I just talked with a buddy of mine who is a retired electrical engineer with 17 years at NASA via text message and he told me why this works. It basically has to do with getting rid of electrical noise (same way as when your stereo whistles on acceleration and you fix it by increasing the ground). Also it dissipates static electricity that builds on the metal body of the TB. Normally this static builds until it is higher than the voltage coming into the TB from the battery and then it shoots out the TB ground wire through the stock plug. However it won't do it until it builds to a point that it can take the path of least resistance. With the housing grounded to chassis, this static never forms.

Makes sense I guess. Anyway this guy knows a hell of a lot more about electricity than I do. But I do know there is a perceptable difference, especially in the way my truck idles...

you can google grounded tb and see the results all around. i used 4 awg and ran it from the tb to the neg post on the battery and my wife has reported a significant change in idle claiming it to be much smoother. she said it isnt completely gone but she can only notice it if she is looking for it. i have yet to drive it to see for myself but it does sound smoother in the engine bay. these guys are grounding their head and transmissions for better signals as well. ill post more later. btw i havent tried cleaning the mass air flow so im going to do that tomorrow to see if it helps more

 

[Goodinblack]

Never heard anything about grounding-out the TB (or anything, for that matter), so keep us posted. Some more info about the theory here would be helpful, too. Thanks.

What was the cure for this?

@KMeloney

Yukon has started doing this

Thank you

 

[Goodinblack]

Bump

 

[Cattivo]

My truck has been doing this ever since I installed the K&N CAI even though I removed it and went back to stock. I have replaced EVERYTHING and it still runs like shit! funny thing is, if I disconnect the plug from the MAF it runs perfect, no rough idle...nothing. As soon as I plug it back in, it immediately begins to run rough to a point where it wants to stall.

I'm ready to sell this POS or drive it off a cliff

 

[Goodinblack]

Mine only does it in drive at idle

 

[jyi786]

My '12 Denali XL had very slight rough idle in drive. Enough to feel it when sitting at traffic lights, but it was not continuous. It would happen randomly every so often, but was unquestionably there.

I changed the oil, which was PURE BLACK (not sure how many times it was changed!), put in 2 bottles of Techron, and drove it 300+ miles to let the new oil and the Techron do its work.

The truck idles so smoothly now that sometimes when I'm sitting at traffic lights, I completely forget my truck is on and think it has died on me or something. It is really that smooth now.

Of course, every now and then, I still feel a slight vibration from the powertrain. It's important to note that our powertrains are supposed to have some type of roughness to its idle; that's what I gleaned from hours and hours of research on many different forums as well.