During "high boost" situations, can suddenly letting off the accelerator cause damage to the turbo? Was accelerating in my old man's truck the other day then had to back out of it quickly and it sounded like a popping/fluttering sound coming from the turbo.

T

 

very contraversial subject. Do a search for turbo flutter and you will find a heated disscussion. IMO it won't hurt anything.

 

I think it can, in most turbos but I m not familiar with the holset bearing design. In other turbos the bearing is not designed for the oppisite thrust load so when you do that, the flutter is air coming back out the intake (backwards) through the turbo thus pushing the oppisite direction on the thrust bearing.....The holset looks to not care all that much...

I d try not to do it a lot but not worry to much about it either.

 

depends on if the fueling is stock or not how bad it hurts it..i mean you'll do more bad letting off at 40+ PSI than 15 or 20 psi stock... ..not advisable either way, sometimes unavoidable though :-

 

Barking the turbo is the fastest way known to man to break the shaft. Especially the HX35 & HX40 turbos because of the small diameter shaft. The cause of the turbo bark is the turbo impeller trying to reverse direction because you closed the intake and the pressurized air has nowhere to go but back out the turbo where it just came from. Talk to Diesel Dynamics, Piers, Enterprise Engine, BD Power, ect.
Bruce

 

FWIW, one thing I didn't see mentioned here is what else may suffer for it in the long run..... the tranny does NOT like the loading/sudden unloading either. That's a good way to loose something important... try to ease out rather than dead drop out... not always possible I know...

bob.