Looking for some help if anyone can. My 05 Dakota has had the engine surging for a couple weeks now. Generally more so once warmed up, rather than immediately on start-up. Will randomly go from 700-1200 rpm, especially when idling in park. Once into gear, it won't do it as often (but still does occasionally) and I'm certain it does it on the road too. In fact, yesterday, my transmission shifted down to 3rd and back up to 5th on flat terrain repeatledly. I'm sure this is connected. Anyway, a year ago the EGR valve was replaced and recently they cleaned out the throttle body hoping that was my problem, but it did not solve it. There is no engine light on and the guy told me he can't figure anything out without the engine light on. Someone else told me it was a vacuum leak, but he couldn't find it and another mechanic said no vacuum leak. Any thoughts...this is killing my mileage aside from being completely annoying.

 

sounds very similar to the problem i had. Take a brush and some electrical cleaner and clean out our throttle position sensor well. Plug it back and she should be fine when you start her up

 

TPS would be my guess as well since you covered most other things linked to the idle...

 

I will agree TPS or the other one with the blue tip is probably filthy. Take that throttle body off the truck, clean the snot out of it, front back, inside, outside. Carefully clean the sensors (treat them like a hurt ****)

 

I would say tps, and the random shifting would explain it. The shifting is based off of speed and the TPS sensor, so if that sensor is throwing random readings, your truck will think the throttle is in a different position than it is. I recommend a new TPS from the dealer, but most aftermarkets will work. I found the BWD one from Advance to work good, Duralast was crap, and now I have a Mopar one and its perfect.

 

Ditto for the TPS...I have this one, works fine:

http://www.amazon.com/Standard-Motor...3171218&sr=1-1

 

Might need to check your catalytic oxygen sensors as well if the TPS is not the issue

 

glad everyone agreed (; seems like a very common problem that a lot of us have experienced.

 

not me lol... "knock on wood" - thankfully I work in a wood shop

 

I had that exact problem. Didn't stop until I changed the idle sensor. Went the same route. Was throwing egr code so I changed egr. Still surged, and I changed TPS. Still surging and I changed the idle sensor next to the TPS and no more surge. And that's my story and I'm stickin to it.