I have a 99 4x4 durango with a 5.2 and I was wondering if anyone could tell me how to fix the studdering problem when i start my truck it sounds like i have a huge hydralic cam in it and i have no clue how to stop it from doing it. I do have a throttle body spacer and cold air intake on it and a super 40 flowmaster but i still cant figure it out i have even take it to the dealership and they cant figure out why it is doing it and it made my check engine light come on and i cant get an inspection sticker till i get it fixed so if anyone can help me it would be much appreciated.

Throttle position sensor?

While not causing your studdering... get rid of that (junk) throttle body spacer. It is snake oil, doesn't help. While sold for our motors, the TB design/setup we have is not helped by added space for the fuel to fall.

To help the studder... it sounds like a lifter or valve. Try changing the oil with Marvel Mystery Oil or something made to suppress chatter. Otherwise a valve job or head job should do the trick.

IndyDurango

These motors are a MFI motor. Carborated motors get help from the spacers.

When was the last time you did a tune up and what parts did you replace and what name were the parts?