What solenoid/lever on the air intake on my 2.5 TDi?

[LayerzA3]

Hi all,

Just trying to work out what this rod/actuator are for on my 2.5 TDI?

The EGR is blanked off but I noticed there is a vacuum hose going to it and a solenoid/valve for that and that goes to a lever on the intake manifold.

I just wondered if these can restrict the air intake if they get stuck and cause issues - I've posted in another thread that I resolved a boost leak which has helped but found this suspect as at one point found the vac line hanging off - at the very least would be good to know what it is as I'm not sure of the best terms to search for it with.

Edit: Hang on is this the EGR flap itself? Even though the piping have been removed I assume this stays in place.

 

[pauldazzle]

Thats the anti shudder valve, which closes the EGR flap on shut down.

 

[LayerzA3]

Took a look at it as I wanted to check the clamp on it and see if there was much muck inside and if open/close. A bit oily but no excessive muck and open.

What I did find was another line with a bolt in it going to another valve/actuator - appreciate any help identifying that. I've found 2.5 TDI noted engine diagrams fun to find tbh.

 

[abyrne153]

The vacuum pipe with the bolt was for your EGR valve which someone has removed. Very common thing to do on these. The anti shudder valve has a couple of functions. It shuts off the air supply to the engine preventing run on when you switch off. It also prevents a diesel engine running on its own oil. This can happen when turbo seals blow and empty the oil into the intake thereby providing the fuel to keep running. I've seen diesels destroy themselves doing this but with the flap closed it prevents this.

 

[LayerzA3]

The vacuum pipe with the bolt was for your EGR valve which someone has removed. Very common thing to do on these. The anti shudder valve has a couple of functions. It shuts off the air supply to the engine preventing run on when you switch off. It also prevents a diesel engine running on its own oil. This can happen when turbo seals blow and empty the oil into the intake thereby providing the fuel to keep running. I've seen diesels destroy themselves doing this but with the flap closed it prevents this.

Thanks - it made a lot more sense when I looked at my spare engine and complete engine bay pics.

I do wonder if that bolt is 100% sealing and might lead to noises I notice at times - easy way to find out/seal tbh.

As neither of these are needed/aside from leaving the butterfly in place to stop runaway would vagcom kick up a big fuss and give me EML's? Looks like a good place for a water meth kit.