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Rough Idle

89K views 93 replies 20 participants last post by  scott17  
you guys have the bad valve seats trust me, I just had it happen to me and got my truck back today with a brand new head and guess what still fucked up. Here is what's going on though when your motor is at idle it builds more pressure within the cylinder which is different from driving that difference in pressure is what causes the valve seat to let go only then and cause the rough idle but when you accelerate the pressure changes and the valve seats and your misfire goes away. If you are under 100,000 miles go to the dealer with the Service Bulletin in hand and tell them to leakdown test your engine.

Do another test for me if you are an automatic trans get on the highway and get your truck and to go in overdrive just when the torque convertor locks up and let me know if your motor seems a little rough then as well.
 
yea what they are looking for is the number for the bulletin so they can pull it up on the computer. so as long as you have that number your good but hey probably won't need it most dealers are familiar with the issue.