see what kind of codes it flashes. cycle the key on and off 3 times and then leave it in the on position. the check engine light will flash. just count the flashes and look up the code at allpar.com or if you have a service manual. i had a similar problem and it ended up being the idle control circut.

 

Last time all that it threw was an egr system failure. I will check it again tho. Can you give me some more info on this?

 

my egr went bad too. a bad egr can cause a miss at idle speed, backfires, loss in power, things like that. could you be more specific as to what further information you need?

 

What and where is idle control circuit, that kind of stuff

 

it controls idle rpm according to engine load. it should be mounted on the drivers side of the throttle body. it's got an electrical connector plugged into it. i'm still in the middle of finding out how to diagnose it. i would recommend finding the problem for sure before you throw parts at it. at o'reilly auto parts an idle control motor is $108.

mine usually bucks when i'm at low rpm's but it comes out of it when it revs higher. when i am backing up it will shudder and rev really low. things like that.