Just recently, id say over the last week, I've started hearing a strange noise on start up followed by a large surge in rpms on startup. It just started happening now that the mornings are getting cold here in WI. Any ideas?

Heres a video of the issue.

 

Rofl, the video was accidently set to private when I uploaded it so now everyone should be able to watch it.

 

Pull the codes and see what's there, looks like the ECU is pumping the throttle to keep the RPMs up, but it could be a lot of things. (I'm assuming that you aren't pumping the accelerator...)
Jim

 

Well it only happens 1st thing during the day when I start it then its fine the rest of the day. Morning temps are around 50 right now. When it was 60+ in the morning it wouldnt happen at all. I'm thinking coolant temp sensor or maybe MAF/TB needs to be cleaned, but the noise sounds like a belt isnt catching.