First of all I would like to say hi to everyone, I am new to this site and it is great, tons of information!

Now with that out of the way on to my problem! I am new to diesels and as I learn abot them I am finding out how different they really are from gas motors. This is my cenario, I have an '04 c/c fx4, the only thing I have done to the engine is add an AFE stage 2 intake, and a 4" turbo back Silverline exaust (no cat). When I accelerate firmly up to 60 mph and above and let off of the accelorator to even out the speed I seem to loose the Turbo pull, I can press the accelerator all the way to the floor and you don't feel or hear the Turbo and the truck will not accelerate. Once this happens, I can completely take my foot off of the accelorator for 3-5 seconds and ease back into it and the Turbo comes back to life. If I stay in the throttle the Turbo will be there as fast as I want to go, just happens when I lift out of it around 60 - 80 mph. Is this normal? Or is my Turbo having issues? Also, could it have something to do with not enough backpressure at that speed for the Turbo?

Any comments or suggestions would be great, thanks.

 

I'm still fairly new to the diesel too, but this sounds totally normal to me. When you let off the accelerator, you've let off the flow of exhaust and lost the turbo. When you step on it again, you just gotta give it a few to get the turbo spooled back up. The one thing I've learned so far is, let off on the gas and you lose boost and it takes time to get spooled back up.
Maybe someone else will chime in here to say I'm right or not.

 

No this is not normal if it is taking as long as you describe. Yes you will lose boost when you let off and the turbo will spool down but it shouldn't take long at all for it to spool back up and take off. I know if I let off at those speeds then mash it to the floor again it rockets off again. Not really any lag.

 

Sounds like EGR Valve problem. Staying open too long. Shut off truck...disconnect electrical connector off EGR Valve then go try it again.

 

I have already disconected the EGR valve after reading other posts about that. I didn't have anything to do with this though!

C'mon people! All of you diesel experts out there and no one (thank you to the ones that have replied) can comment on this?

 

Thanks, but I have already disconnected that!

C'mon people! All of you diesel experts out there and no one can seem to help, or expierienced this? (Thank you to the ones that have replied)

 

I am having the same issue, anybody have input?