What does this connect to? (7A crank case breather)

[steve briance]

Hello all,
It has been quite a while since i have had a factory crank case breather on my 7A but today I have reinstalled it in the hope that i can set it all up to once and for all sort out the intermittent idle droop like all 7A's seem to suffer. I figured that the engine didn't suffer the issue from the showroom so a thorough refresh and confirmation there are no vacuum leaks anywhere stands me in the best position to sort it...

There is one problem though, i cant for the life of me remember where all the connections go! I have searched for PCV diagrams and find some claiming to be but, they are clearly not 7A engines. 3B also not the same so im stuck.

Anyone confirm where the small hose from the breather connects to? I think it is the throttle body but would appreciate a second opinion.

pics of what i mean to help.

[Bowie69]

The block breather nipple is capped off.

The one on the throttle body goes to the carbon canister, I think, via a metal and nylon pipe.

[steve briance]

I know the metal and nylon pipe you are thinking of but from recollection that goes from a connection under the rubber pipe to the (bosch) ISV and then to the carbon canister. I'd had the throttle body connection blanked off when running no breather, maybe I'll just blank it off again and blank off the small metal pipe as well.

Looking at the layout; The bigger pipe from the breather goes upstream of the throttle body and the small connection is down stream of the butterflies in the TB. This makes me wonder if it is important to add a small amount of extra air for idling purposes?...

[steve briance]

Look what i found, you have to love a bit of late night Audi factory manual browsing!

This answers my question perfectly, hope it helps other 7A owners out there (if you are still running breather system)

[Mikes2]

I'm guessing yours is a late car as per that diagram - same as mine. That's how mine is set up from breather to throttle body

[steve briance]

Yep, it is a late car. Just been out in the rain sorting out the engine for its first run. The good news is, the engine runs and with the vacuum and breather lines connected as per diagram, it idles perfectly. Not driven the car yet but the signs are good.