Alxx Nova

Looks like the nipple has cracked and it is too short to stay inserted into the hose and I need to replace it. So …

What is it and what’s not working right with out it? Would it be okay to replace it with a tube until I get the replacement part?

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Alex Portanova
1989 944 N/A
1999 Chrysler 300M
1992 Harley FXSTC

Techno Duck

That is a vacuum check valve i think, with that broken you basically have one relativley large vacuum leak.

Why the hell am i still awake?

hpservertech

Hay i'm still awake!

Doesn't that connect up to the brake booster?

Alxx Nova

I thought it might be a check valve though it's larger then what I'm used to seeing on other things.

It's connected to two canisters on the fuel rail.

Heck I'm up because I just can not turn off a Godzilla flick that's on the SciFi channel.

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Alex Portanova
1989 944 N/A
1999 Chrysler 300M
1992 Harley FXSTC

FRporscheman

I don't think my early NA had that. You should at least remove it and replace it with a tube. Otherwise your FPR (canister on the rail) won't be working and your engine won't be happy...

I guess it could be one of those passive valves that only allows flow in one direction... but why would you need that on a vacuum line? My guess is it's a damper for vacuum/pressure changes. I don't think it's a valve because valves are usually activated by a signal, and there's nothing else connected to it.

I checked my PET (which is for '88) and I couldn't find it.

Why am I still up? Because Conan the Barbarian just finished and I'm trying to find a way to get my 2 hours back. I guess I'll try the search function.

TheRealLefty

Yes, I believe the broken part is a vacuum check valve and yes you now have a huge vacuum leak.

This is a one-way valve that connects the climate control vaccum system to the manifold vacuum. If you simply patch the line for now, you will not negatively effect engine performance, but you will only get heat under acceleration and load. How do I know this? Mine broke at exactly that same spot and I've been driving my Turbo S without one for over a year

"Seriously officer, my windshield was frosting up and going faster was the only way I can get it cleared...."

special tool

This is correct.

Also - if this WAS connected to the FPR, you need to double-check your entire vacuum system, because obviously an idiot has had his hands on it.
The vac. to the FPR is one of the most important circuits on a 951 - you will blow a headgasket without it under boost.
It should be checked at every oil change.

lleroyb

Here is a diagram for an NA that shows the check valve. I replumbed my 951 to move the check valve away from the engine and any movement. You can find generic ones at the autoparts store much cheaper than the Porsche part.

Lou

Techno Duck

The '83-88 944's had that coming right off other check valve on the brake booster. In '89 they moved it to in between the firewall like the 951's. And if i remember correctly it t's off to the FPR on one end.

lleroyb

Is that the stock configuration for an '89 NA? I wonder if the brake booster fitting is still there to be able to go back to the earlier configuration. There are so many places the climate control can become a leak. I have seen the line disconnected to the reservoir too many times. Seems like it would be better to separate it from the FPR as much as possible.

Lou

Techno Duck

The check valve on the '89 brake booster is is different and does not have the nipple on the end of it.

Whats funny is that picture looked exactly like my friends '89 which had the check valve broken in the same way.

Alxx Nova

I took somemore pictures. These are from the other side. You can see how it connects in the first one. The second picture shows the canister at the front that it connects to also.

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Alex Portanova
1989 944 N/A
1999 Chrysler 300M
1992 Harley FXSTC

Techno Duck

Front one is the fuel pressure dampener, second (closer to the fire wall) is the regulator.

Fix that ASAP as your fuel pressure is going to be a bit funky and can cause some problems down the road.

Alxx Nova

Thanks

So any vacuum check valve will do. That's cool. I'm going to use a vacuum tube connector for now untill I get over to autozone for a new one. Thanks again.

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Alex Portanova
1989 944 N/A
1999 Chrysler 300M
1992 Harley FXSTC

FRporscheman

Oooooh, yeah I remember seeing that thing over there. Thanks T-duck!