Strange noise

[dhanna6powerstroke]

I've got an issue with a strange noise. It sounds just like a super charger does when it's building boost. Seems to be boost related and has something to do with engine temp. It doesn't do it until the ECT gets to at least 140 and when the boost gets to about 8 psi. Gets louder as boost increases and noise goes almost completely away when shifting between gears. I see the same amount of boost but doesn't seem to have the right amount of power when noise is present. I've checked everything from boots to the plastic cold side tube. I have no clue where to look. I was wondering if the VGT could be commanding the vanes open farther to compensate for a leak? Any help is appreciated.

[dhanna6powerstroke]

Can anyone help me with this? Don't know where to start looking.

[dannyboy950]

Check your map sensor & hose and the hose bib. Also your ebp and tube for plugging.

Sorry all I can think of offhand my brain is fried gonna go get some sleep if I can.

[dhanna6powerstroke]

I've checked the MAP sensor and hose and the it's good. Never thought about the EBP sensor and tube. Didn't think it would cause an issue like that but I'll pull it today.

[dhanna6powerstroke]

This noise is driving me insane. I've been watching my VGT% and at WOT it will drop into the low 40's when the noise isn't present and only 50's when noise is present. When the noise is there, I can turn my high idle on and the turbo screams. I've checked the clamp that holds the turbo halves together and everything. Can't feel any air leaks at or around turbo. I have no clue.

[RedneckYankee]

Just a thought check the bolts on your EGR blank off plate. Mine backed off and caused a strange sound when turbo spooled up. Maybe wrong but worth checking.

[dhanna6powerstroke]

Originally Posted by RedneckYankee

Just a thought check the bolts on your EGR blank off plate. Mine backed off and caused a strange sound when turbo spooled up. Maybe wrong but worth checking.

I now have an EGR delete but valve is still in the intake.

[SuperDuty2004]

how many miles are on the turbo? you think it could be a bearing? have you recently done any work to it? is it like a roots style sound.. like a high pitch kind of vibration?

[dhanna6powerstroke]

Originally Posted by SuperDuty2004

how many miles are on the turbo? you think it could be a bearing? have you recently done any work to it? is it like a roots style sound.. like a high pitch kind of vibration?

Sounds just like a roots style charger. Turbo has less than 15k miles on it. Not saying it's not a bearing but I've never heard a noise come and go in a turbo with a bearing failing.

[SuperDuty2004]

Originally Posted by dhanna6powerstroke

Sounds just like a roots style charger. Turbo has less than 15k miles on it. Not saying it's not a bearing but I've never heard a noise come and go in a turbo with a bearing failing.

well, i'm not sure either. but when boost comes on, im sure there is a lot of side pressure on the bearings, only when boosting. Maybe you can try having a buddy rev the engine and do the old oscilloscope trick with a screwdriver and see if you can pinpoint where its coming from.