Whistling/humming from under the hood or dash

[Philsky]

Hey Fellow diesel lovers, On saturday my 6.5 Suburban started making a whistling/humming sound. At first I though tit was coming from the Hvac system, but now i think it might be coming from the elbow thta mates the turbo to the airfilter box.

It doesn't start making any sounds until about 2000rpm. but it only does it when the engine is under load. I have popped the hood and reved it to red line with no luck but when in gear it screams at 2k rpm.

It was suspected the Turbo was sucking air in through the small elbow that pops into the Airbox elbow.

Has any one else had this proble? Does any one have any ideas on how ot make this go away? any help would be greatly appreciated.

Phil

[DennisG01]

It could be that elbow - being loose and allowing you to better hear the turbo spool up. Check where the rubber elbow attaches onto the plastic elbow. On mine, the bottom side of the plastic elbow is crimped (must have been from previous owner over-tightening) and if I screw the hose clamp on too hard, the rubber elbow actually starts to slip off.
In this case, the only problem is that you could suck in debris.

[tommac95]

Not to be real negative, but if you take off the elbow, check the turbo shaft for play (engine off cold), and look carefully to see it isn't/hasn't rubbed/abraded the housing.