Turbo Whistle at Start-Up ????

[Gordon Gould]

I recently bought a used 2012 M5640SU with a V2403 engine and it has 700 hrs on it. It is the first turbo charged diesel I have owned. Often on start-up, and especially when cold, I hear a short fairly loud whistling whooooosh type noise which seems to be coming from the turbo. I did not hear this when I test drove it. Is this normal or is it a sign of bad things to come? Not knowing is driving me nuts. Thanks !!

gg

 

[Snobdds]

Do you know if the turbo is a VGT (variable geometry turbo) or a turbo with a wastegate? A VGT will usually cycle the vanes to make sure the unison ring moves freely. A wastegate will dump the excess pressure if not needed.

All my turbo vehicles whistle at start up and then either adjust the vanes to adjust pressure or the wastegate will open and dump the pressure. Each will make a whoosh sound. Sounds pretty normal to me...

 

[Gordon Gould]

Thanks for the help Snobdds. I believe it is a waste gate from some info I found on line. I guess I have something new to learn about. It is a relief knowing it is probably normal - sounds so weird to the uninformed.

gg