I've got a '72 1.7 and I'm replacing all my vacuum hoses and I've come across something that's got me stumped. While replacing the hoses, I found that the hose coming from the front of the deceleration valve (the connector pointing in the direction of the front of the car) was simply lying on top of the engine not connected to anything. This probably explains the backfiring issue I was having.
Where does this hose connect?

This pelican parts diagram that everyone keeps mentioning doesn't even have a deceleration valve: http://www.pelicanparts.com/914/technical_...4_17FI_diag.htm

The diagram I got with the hose kit from Auto Atlanta shows that hose is connecting somewhere near the aux air regulator, but I don't have any extra connection ports there.

Anyone know where this hose connects?

Thanks!

Have you looked at all the diagrams at Bowlsby's site?

https://bowlsby.net/914/Classic/TechNotebook.htm

He doesn't have a diagram for a 1972 1.7L though. On my 1974 2.0L, that connection goes to plenum via an F connector that also connects the PCV valve.

https://bowlsby.net/914/Classic/zTN_FI_Hose...3-Early1974.jpg

That's the exact diagram Auto Atlanta included with the hoses.

I'm not quite understanding how the hose from the deceleration valve connects right there. There's the short hose from the aux air regulator to the intake air distributor, but that's the only connection I have there.

Does the deceleration valve connect directly to the intake air distributor, or somewhere else?

One connection to the air cleaner, and two to the manifold (AKA plenum or intake air distributor). One large and the small hose connect to the manifold, and the other large hose to the air cleaner.

--DD

As I said, I only have the one connection for a short 12mm i.d. hose from the aux air regulator to the intake air distributor/manifold/etc whatever you want to call it. Where does the hose from the deceleration valve connect???? I have no other connectors in that area.

As boxterfan said, it connects to the plenum via an F shaped connector. The hose from the pcv valve also goes on the f connector. The aar connects to the air filter box

Sorry for the frustration. I think I'm confused because I'm getting conflicting information from different people and from reading through different threads on here.

So I found this diagram, and apparently the part I need is #4, which does in fact T off of the aux air regulator like on Bolwsby's diagram. Unfortunately it's not currently available
http://www.autoatlanta.com/porsche-parts/h...rts§ion=117-15

On a 1.7, there IS NO "F" shaped connector. There's a 12mm rubber connector between the AAR and the intake plenum, and that connector has a 3mm leg extending at about a 30-45 degree angle. A short steel tube fits onto that leg, and the vacuum hose slips over that. The pre- decel valve cars use a piece of cloth braided 12mm hose in place of that connector piece. IIRC, that piece is NLA, so most folks use the "F" hose connected to another port as a substitite, putting the pre-decel version hose in place of the original coupler. NOW are we clear on this?

The Cap'n

Well,
I have one on my 1.7 and now I am even less clear on how it is hooked up, but thanks, I know mine is right, you just managed to make my head hurt......

There's a plastic "Y" in there, I think. You can make an equivalent piece from plumbing bits if you search for a little bit.

--DD

As usual the Cap'n is right. The f connector is for the 2 litre. I have several of the plastic "y" connectors. Haven't messed with a 1.7 in a while.