Thread: L322 td6 turbo noise

yes, that's right. The 3rd barb goes off to a breather with filter.

From what I read on FFRR (where they are replacing them), the breather is to release the vacuum quicker as the EGR requires less vac pressure to operate (closer to atmosphere) because it doesn't have the strong return spring that the turbo has (also why it needs the reservoir). Pressure is controlled by the PWM signal from the ECU. Plug it up and off you go - or leave the breather there. On the turbo side - without a breather it is relying on atmosphere leakage to release the vacuum - which according to the test gauge, that strong spring does well to drag in - If you look at the valve bodies they look exactly the same with exception of that extra outlet .

I haven't tested it - only difference could be removing vacuum as apposed to applying vacuum with voltage, from what I read that's not the case - mine was ok and the EGR valve is in the box of spares - so I would suggest a test first. Actually I could do this quite easily if wanted.

I have unplugged the wiring plug from the turbo control valve whilst the engine was on idle and the turbo quietly went to sleep. Plug it back in and the growl/whine starts up again .Mind you it is nowhere near as noticeable when engine is hot. Is the boost control valve a simple on/of or is it variable via different voltage?.

Originally Posted by theelms66

I have unplugged the wiring plug from the turbo control valve whilst the engine was on idle and the turbo quietly went to sleep. Plug it back in and the growl/whine starts up again .Mind you it is nowhere near as noticeable when engine is hot. Is the boost control valve a simple on/of or is it variable via different voltage?.

It's variable - Pulse width modulation control. - What voltage have you got at the plug, I can check mine if you like?

Thanks Harlie. Wont be home till monday . I will check the voltage then and hopefully my vacuum test kit wont be far away.

Hi all . A while since last update . Turbo removed and off to repair shop. The guy says from what i am describing it definitely sounds like exhaust manifold leak or egr etc. After triple checking with inspection camera all gaskets AOK . I tell to go ahead and strip it down which entails a rebuild as he wont reassemble old seals and bearings. Thats fine. Rang him Friday and tells me something has gone thru my turbo and taken a chunk out of my exhaust impeller hence the noise i have. Told me either injector or glow plug most likely. Mmm injector highly unlikely as it runs smooth and plenty of grunt so out with glow plugs . All glow plugs in tact . WHAT THE ?????.

Originally Posted by theelms66

All glow plugs in tact . WHAT THE ?????.

Probably one of those lost 10mm Sockets that every one loses

Yeh good on ya I still have to put it back together.
That reminds me i better buy another socket .

Just reading up on the bmw site and most of their diesels ran swirl flaps that fail and cause great damage to valves pistons and even turbos .wait did i say TURBOS . Quick check it out .But the td6 manifold doesn't seem to run them . Anyone got any ideas .