Hello,

So I just bought, last Saturday, a preowned dodge certified 2008 Ram 1500 Hemi 5.7. 34k miles. Fully warrantied, so I am wondering if this is an issue. Truck has been running no issues at all. However, last night was really cold in NY, about 10dgrs. Trucks started fine this morning but when I pulled out of my driveway, the RPM's jumped to like 2500 when i touched he gas then back to 1000 and the jumped again anytime i hit the gas, drove like this for about half a block, which was a little scary. Then, when i hit the gas again, it stopped reving up and drove normally, and has been running fine since. I didnt let the truck warm up to much, only about a minute or two, think that it being so cold and me not allowing it to warm up fro several minutes was the issue? Like I said, I only own it a week and its been cold but not that cold, and I have been letting it warm up longer. Just asking to see if it may be something other than fridged temps and if so, how long do you allow the hemi to warm up for? PS winter MPG sucks, cant wit for summer gas! 14mpg highway

 

It should not do this. I wonder if the throttlebody needs to be cleaned and is sticking a little when cold. My 08 has never done this.

 

No idea... only did it once, tonight i drove it from cold and had no issues at all, drove fine. It is 14dgrs out right now, truck drove fine... let it warm up for 5 minutes and no issues. Maybe a freak thing I hope, well see tomorrow morning I guess. Another cold night. If it keeps going it, ill for sure take it back to the dealer.

 

Could this be the trans slipping a little when cold? Check the trans fluid level.

 

Did it sound like the fan was kicking in? If so, it was the fan clutch engaging. It happens all the time when the engine is cold and you jump in and drive.

 

The fan clutch has nothing to do with the idle speed jumping up to 2500rpm.

 

I didn't have such issue with my truck. It parked outside and even if temperature -20C it starts fine. I give couple of minutes to idle before I'm going. We had one thread before when such behavior, jumping of RPMs and accelerating without any reason was discussed, so it could be an issue that is not related to the cold.

 

No reason for the fan clutch to engage in temps that cold. No cooling is needed then.

 

Truck just was certified by Dodge. They "apparently" go over all the fluids and check everything over, change the oil and brake pads, got new tires, inspect it, and all that. If it happens again, I will take it back. Drove it yesterday all day, stop and go and highway, was about 22dgrs, no issues. I dont know what happened. Maybe the throttle body did get stuck and caused it. Guess we will see.

 

I realize that, but it does engage at start up. My Dakota did as well. It sounds like a jet airplane when you start it up. Once the clutch disengages, the rpm's go down.