Trouble finding the EGR valve... Pictures or diagram?

[backtosand]

I have an Audi A4 2.8L showing a P0401 trouble code. Haynes repair manual does not show the location of the EGR valve or the parts immediately around it. Can anyone help with a picture or a link to an engine diagram? Many thanks.

[AudiMick]

Originally Posted by backtosand

I have an Audi A4 2.8L showing a P0401 trouble code. Haynes repair manual does not show the location of the EGR valve or the parts immediately around it.

Can anyone help with a picture or a link to an engine diagram? Many thanks.

Only on the 96-97 12 valve V6.

Rear of Bank 2 under the cruise control vacuum tank.

If you are getting an EGR insufficient flow, do not replace the valve.It is the EGR passage between the valve and the manifold that is blocked.

This is a recurring problem with the 12 valve and changing the valve doesn't fix it.

[Old Dog]

Originally Posted by backtosand

I have an Audi A4 2.8L showing a P0401 trouble code. Haynes repair manual does not show the location of the EGR valve or the parts immediately around it.

Can anyone help with a picture or a link to an engine diagram? Many thanks.

Here is a link to another AudiMick reply dating back to Dec 2008 detailing a little further on what needs to be done plus a bonus pic .

http://forums.audiworld.com/showthread.php?t=349809

You should, in the future, do a search first before asking for help. If you are unsure what is the best way to do a search, I'd be more than happy to help.

Good Luck!

[backtosand]

Thanks for the assistance. You mention a link but I don't see it. Please repost.

[Old Dog]

Originally Posted by backtosand

Thanks for the assistance. You mention a link but I don't see it. Please repost.

Woops sorry. Must have had a senior's moment . The link is now included where it should have been in the first place.

Take care.

[backtosand]

Originally Posted by Old Dog

Woops sorry. Must have had a senior's moment . The link is now included where it should have been in the first place.

Take care.

Thanks, Old Dog and AudiMick. The info helped greatly.

New question: On the floor of the black plastic air duct behind the throttle body is a 2-inch rubber "flapper valve" that allows recirculated gases to enter the intake manifold under positive pressure (my guess anyway). The mat is torn and non functioning so I removed it. Replacement of the entire duct piece with a new rubber valve is roughly $130. How important is this valve? Any harm if I operate without the piece in place?

Note to other ham-fisted DIY's: You will pay dearly for breaking the plastic hoses that lead into the air duct behind the throttle body, as I have done. They are quite brittle. Replacement cost is more than $120 for each hose!

[AudiMick]

Originally Posted by backtosand

Thanks, Old Dog and AudiMick. The info helped greatly.

New question: On the floor of the black plastic air duct behind the throttle body is a 2-inch rubber "flapper valve" that allows recirculated gases to enter the intake manifold under positive pressure (my guess anyway). The mat is torn and non functioning so I removed it. Replacement of the entire duct piece with a new rubber valve is roughly $130. How important is this valve? Any harm if I operate without the piece in place?

Note to other ham-fisted DIY's: You will pay dearly for breaking the plastic hoses that lead into the air duct behind the throttle body, as I have done. They are quite brittle. Replacement cost is more than $120 for each hose!

That valve effectively acts as your PCV , it allows the blow by gases to be vented into the intake , removing the (non return) valve allows air from the intake to be drawn into the crankcase.

I don't know if it will cause a problem. Some people have spliced in regular "autoparts store" PCVs into to the vent lines to maintain the correct pressure relationship. Some have modified the system and gone with a catch can, which is better since it stops the EGR re-blocking up.