924Board.org

[Chrenan]

Hello,

I have edited Jon's diagram below to show how the small vacuum lines on my 1980 are routed. Basically, I am missing the 3 "T-connectors" for the small vacuum lines, and these lines are routed according to the red paths in the image below. Is this a problem? I never really noticed it before, I replaced all the lines as they were when I got the car and never thought about it again until I saw Jon's picture...


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1987 951 - M193 Version for Japan

[Smoothie]

One problem that's looking pretty obvious to me is the line you added at the very top. You'd need a vacuum source to operate both the distributor and the EEC purge valve ("vacuum valve" in the diagram), but instead, you have them hooked together, so neither one would be operating as they should.
That distributor port should get vacuum from the intake manifold (that'd be downstream of the throttle).
The EEC control valve should get vacuum from the TB just upstream of the throttle valve. My car has the line from the EEC valve going first to a water temperature controlled valve (something like what's labelled "vacuum switch in coolant line" in the diagram), then on to the TB. That delays purging of the charcoal canister until the engine's warm. If you have an unconnected water temp valve you could use it, but I don't think it's absolutely necessary to.
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[Chrenan]

Hmmm,

I've updated the above diagram. The connection in the red box is the only one that will cause me trouble. All the other ones I can replicate with a few T connectors. The hose between my Intake Manifold and Auxiliary Air Valve has no opening for a small vacuum line, it is just a regular solid black hose. Any ideas.....?
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1987 951 - M193 Version for Japan

[Smoothie]

I don't know exactly what you have to choose from. Any line that leads back to the intake manifold will do.
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[Chrenan]

All done.

Bought some T-connectors at Canadian Tire, and also a joint I was able to insert into the hose in the red box. Everything is connected to spec, timing and idle checked. Not too hard at all...
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1987 951 - M193 Version for Japan

[alxch1n15]

so is that picture as it should be? if it is, and 80's are the same as 81's, then i need to do some re-hosing
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'81 924 n/a

[Chrenan]

The picture below is as it should be, however I am not sure that 80 and 81 are identical...


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1987 951 - M193 Version for Japan

[isuras2]

It seems that my car's vacuum hoses are identical, except that my car doesn't have the "vacuum switch in coolant line" or the small hose from the "vacuum limiter" to the T connection. My distributor hose from the back of the distributor (top of picture) goes directly to the T connection between AAV and Intake Manifold. How will the car be affected without the "Vacuum Switch in Coolant Line" and small line from the "Vacuum Limiter"? I am also having trouble getting to the connections for the brake booster hose (not the one on the booster itself) and airbox (from charcoal cannister). Any suggestions?

Thanks,
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Rob
'80 931 (sold)
'80 924 NA (sold)
Former Omaha Crew

[Chrenan]

OK, here are a few tips that might help, keeping in mind that I'm not sure the 1980 and 1981 are the same as I think the 1981 has an updated ignition (DITC?).

The "vacuum switch in coolant line" is hard to find, you basically stand on the side of the car with the distributor, and look down along the far side of the distributor. The "vacuum switch in coolant line" is mounted quite low and is a little hard to see, but it actually looks very similar to the pic in this thread, with two little "bunny ear" pipes coming out of it.

The small hose connects to the "vacuum limiter" on the underside of the vacuum limiter, you can't see it from the top. Easiest thing to do is remove the "vacuum limiter" from the intake manifold, connect the vacuum line to the little pipe sticking out the bottom, and then re-install the "vacuum limiter".

The airbox vacuum connection can be reached from underneath the car. To get to the brake booster hose connection at the Y-Pipe, you'll have to remove the Y-Pipe to get access as the brake booster hose connects on the lower side.

I would check your vacuum picture on you driver's side fender under the hood to be sure that things are to spec...
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1987 951 - M193 Version for Japan

[ReicheBrown]

will that diagram work for an 82?
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1982 924 NA
(painted a friends house for it)

[isuras2]

I'll check the vacuum picture. I'll look for the "vacuum switch" and connect a small hose to the "vacuum limiter" tonight.
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Rob
'80 931 (sold)
'80 924 NA (sold)
Former Omaha Crew

[Smoothie]

Actually you should have the "vacuum switch" (it senses coolant temperature and opens when the engine's warm) - that should be attached in-line with the small vacuum control line to the EEC purge valve "vacuum valve". That top line to the distributor should lead to the intake manifold with no switches or valves in its' path. Everything else looks good. Vacuum sources to each component are correct - just take the vacuum switch out of the distributor line and have the EEC line run through it instead.
Like this - http://pg.photos.yahoo.com/ph/smoothies931pics/detail?.dir=341f&.dnm=f1db.jpg&.src=ph

[Whoops - never mind that...after getting a look at a US-Canada '80 NA vacuum routing sticker I see that for an '80 NA, that line to the distributor is supposed to go through the vacuum switch (on my own car, it's the line to the EEC purge valve that goes through the vacuum switch - ,but my car doesn't have vacuum advance/retard) - so although I now believe it doesn't matter a whole lot whether you have the vacuum switch on the distributor line, the eec purge valve line, both or neither (given that some cars have it in one place, others in another and still others don't use it for either) in the interest of keeping things stock, obviously go by what it says on your sticker (if you have one).]
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[ReicheBrown]

Where might i find replacement vacuum line and what are the three diameters i need. I think my plastic lines are good and my large hoses that go to the charcole are fine. It is the middle sized ruber ones that are cracked. I have ade due with some fish tank air pump line for now the car seems to run smoother.
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1982 924 NA
(painted a friends house for it)

[isuras2]

I went to the local auto parts store and got hoses that work. Does anyone know if the hoses from the venturi tube to brake booster, air cleaner and intake manifold molded hoses or will any hoses that can make those connections work?
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Rob
'80 931 (sold)
'80 924 NA (sold)
Former Omaha Crew

[Chrenan]

I just used regular hoses, but make sure you leave enough slack that they don't bend and kink.
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1987 951 - M193 Version for Japan