awdinut

one of the two on my '04 V8 that change the manifold length has a bad diaphram. Car-part does not list that item, and yards wont take parts off of a good engine, so I dont know if a used one can be had. But I hope so because a new one is $400 !! Any ideas ?

storka

Hit the eBay pages

awdinut

There are only new ones on eBay.

storka

Look for the ones that are selling engine components from wrecked engines.
And ask them the question.
I have found with eBay if you are patent the item is found sooner or later.

the_duke

Audis4parts.com

probably won't have parts for an A8 but they most likely will for an A6 C5.

2001 S8

Check out the link below. It's interchangeable. Best price I could find.

Lamborghini DIAPHRAGM | 077907327A

Good luck.

awdinut

looked on car-part for yard selling other engine parts and called...got one for $35 shipped ! Another yard wanted $180, so it pays to shop around.

richard-tx

Those diaphragms are very similar to the cruise control diaphragms used on almost all the Audis from about 1990 to date. If you search scrap yards, you might find something that will work for about $5.

MP4.2+6.0

If yours was torn by the way, really check the operation of the flaps carefully. Thus, potentially it is a symptom but not core problem. Make sure the key shaft that goes into the manifold is free to move--against the spring pressure that is. If it was stuck, it could be why the vacuum eventually tore the diaphragm. On my prior A6 4.2, the diaphragms and plastic links all survived, but eventually the shafts froze up and could not be repaired successfully. Some penetrating oil on the outside of the shafts at the pivot area can help marginally, but not permanently.

Mister Bally

M '81 4000 5+5 (5 cylinder engine) had the same looking one for it's' cruise control.