My 2004 did the same thing a few months ago. It was the accelerator pedal assembly, fixed free under warranty, even though I have more than 36,000 miles on her. I believe there are 3 switches in it and if all 3 don't read the same the engine drops to idle. Scary feeling isn't it?

 

No I did'nt. The reason I did'nt was because I was turning at the stop sign then making a turn as soon as I turned. I was watch a couple cars coming toward me. I more less "felt" the problem at first. I did notice the sound and the postion of the tac. By the time my mind cought up with me so did the engine. I did notice it was putting out black smoke, not alot but just like if I where to take off really hard.
For what its worth this truck doesnt sit at all. Its driven everyday. At least 15 miles one way. Its 30 miles to work one way. It gets to operating temp everyday.

 

Reading your post actually made me think. I dont think it would have mattered if I did look at the boostgauge cause I'm pretty sure it was at 0. If the engine is idling then the turbo is'nt boosting or at least not enough that registers on the gauge. Which puts it right back at a possible pedal or sticky vanes.
Did your truck pick back up like mine did, or did you have to have it towed to the dealer? But that is what mine did it dropped to idle the first time cause I was going down the road, and this time it would'nt leave idle.

 

15 miles is not very far, Have you pulled anything heavy? or really gotten in the throttle and worked the engine hard? Do you idle for long periods? or drive 15-30 miles and let it set for a 14hr day, then drive another 15-30 miles?

 

On the 7.3L that I had it was an early warning of the cam position sensor getting ready to fail.

TG

 

No 15 miles is'nt very far but the engine gets hot. Really only sat and sun I only travel 15 miles 1 way. Yep I drive 30 miles its sits from 8-16 hours then drives another 30 miles and sits for another 8 or so hours. Yea I pull something heavy pretty much 3-4 times a week on the off season. My truck however sees heavy loads 7 days a week several weeks straight. No I dont get on the throttle or idle for any peroid of time, maybe just to check a fence or open a gate or throw off a bale of or 6.

 

Brother here I am again. However I think I'm alittle prepaired this go around. Now this problem started out of the blue went away did'nt show its face for another 5 or so months. Then around 3 months later did it again then a few weeks it started doing it weelky to daily. Yep now it does it once a day.
Heres the situation. If I'm cruising and drop my speed pretty steep, to go over a railroad track or make a turn then get back of the acculator what I thought was no response is really the rpms are slowly going up but the turbo is not putting out, then all of a sudden at 2000 rpms the turbo boost. It jumps over 10 like you stepped on its tail. Mind you this does'nt happen but once a day. So its not every time I slow down, but everytime that I've had my mind on it, it was the same. I'm thinking that on the time I said I was stopped I believe it was a rolling stop. When I'm saying slowing down I talking about 50-55mph down to 10-20mph then back on the petal. I have watched my boost gauge everytime the last 3 weeks and its sitting on 0 untell 2000 rpms. Please tell me this is some kind of freaky turbo lag. Any if anybody has any more input please chime in.

 

Your turbo is in need of cleaning.Clean the turbo before it over boosts and lifts the heads.The procedure is in the 6.0 bible.

 

Sticking VGT... my .02