W212 E350 CDI brief (10 minute ish) turbo whine.

[ALFAitalia]

As you might know I've only had this car for a few weeks... so far no issues. However today when I was on my way home I noticed the turbo whining... which got louder for a couple of minutes until it was fairly loud... then after about 10 minutes it was gone as quick as it came. Car drove like normally throughout. Any ideas? I wonder if it was going through regen... the first one in my care....but my old derv ALFA only gained a slightly louder exhaust note during regen...no extra turbo noise... so if its not that then what? Thanks in advance for any advice.

 

[W1ghty]

Might be worth taking the batwing off and looking at the front inside of the turbo , also check the orange turbo seal is seated correctly .

 

[ALFAitalia]

Funny how it came and went though.

 

[W1ghty]

Funny how it came and went though.

Yes it is .

 

[st13phil]

I wonder if it was going through regen

If it was going through a regen it would be holding the lower gears to keep the engine speed up. I don’t remember any accompanying turbo whine when mine did a regen though.

 

[ALFAitalia]

Well that was an easy fix....if a temp one. It started to whine again tonight....so I stopped by the side of the road and pulled off the engine cover and it was obvious. The sensor in the batwing near the turbo (not looked up what it does yet was loose......getting my son to rev the car it would move in and out depending whether there was a vacuum or pressure. Gods gift to bodgers...the cable tie was employed to keep it tight in....silence. I was dark so there will be a proper repair when I figure out what is supposed to hold it in....which was not obvious at the time! Just seemed to be jammed in with an orange seal.
Bad pic below...Anyone know what this sensor is (pressure perhaps?)....it right by the turbo intake.

 

[W1ghty]

Well that was an easy fix....if a temp one. It started to whine again tonight....so I stopped by the side of the road and pulled off the engine cover and it was obvious. The sensor in the batwing near the turbo (not looked up what it does yet was loose......getting my son to rev the car it would move in and out depending whether there was a vacuum or pressure. Gods gift to bodgers...the cable tie was employed to keep it tight in....silence. I was dark so there will be a proper repair when I figure out what is supposed to hold it in....which was not obvious at the time! Just seemed to be jammed in with an orange seal.
Bad pic below...Anyone know what this sensor is (pressure perhaps?)....it right by the turbo intake.
View attachment 163354

Good job , I zip tie mine as well .
It’s the Postive crankcase ventilation pipe

 

[W1ghty]

This sort of thing . Looking at your pcv , I think there is an updated one with a better orange seal fit .

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