35i Whining / Vacuum Cleaner like Noise

[Lurcher]

Cracked charge pipe best odds....

[NoQuarter]

Originally Posted by Lurcher

Cracked charge pipe best odds....

With no boost codes?

[Lurcher]

Originally Posted by NoQuarter

With no boost codes?

cracked vs blown up.... possible with no codes?

Easiest thing is old mechanics trick of using a piece of tubing and hold to your ear and start chasing the sound in the engine bay with the other end. That would help with the troubleshooting.

Everything is not solved/troubleshot with OBDC Old school....

[NoQuarter]

Originally Posted by Lurcher

Everything is not solved/troubleshot with OBD Old school....

I love my stethoscope! Simple metal rod with rubber tubing.

I really like my local svc center team - but it annoys me to end that generally svc techs won't troubleshoot anything unless their is a code and predefined process of what to replace first.

BMW centers are great at following BMW repair procedures, but real troubleshooting not so much. Once you find a good tech and SA stay with 'em!

[emrdzy]

Since that noise is not there while in neutral mode it is difficult to apply old school methods.

[Lurcher]

Put it on a lift and spin away....

[Zyal8r]

I do have an N54. It doesnt sound anything like that recording. My own experience with a sound like that was not an N54 though.
I am puzzled that he had bmw tech say it was normal. There may be better info on forums for BMW models other than Z4 that also have Turbos.

[NoQuarter]

At the moment, he has no idea what mods are on the car so all this speculation is kinda pointless.

If it turns out there are some of these modifications then it is indeed normal to here the turbos easier.

If the sound being heard is that loud and not "normal" then there should be a big enough vacuum/boost leak that the DME would detect that the boost being requested is not being hit.

If he reports there are no modifications then certainly more investigation can be made. Won't be THAT hard to determine where it is coming from normal or not.

Simply unplugging the turbo solenoids is a good place to start.

[emrdzy]

I tried to check some parts of the engine exhaust but everything seems like stock. Well, I am not that much pro about modifications so I am not %100 sure.