need vacuum diagram for my 84 4000 quattro

[onlyaudis]

someone really messed up the vacuum lines on my car,(cruise disconnected, so odd looking T fittings, etc) and there is no vacuum for the dif lock system right now (we manual activated them and they do work and the lights come on) I need a good sized vacuum diagram so we can redo some of the hoses and get the vacuum to my dif lock system again. can't find anything so far, any links to online docs would be great, and if anyone has the real Audi service bible and could scan the vacuum diagram, i would be very thankful Andy

[Rogviler]

It's REALLY hard to scan the Bentley, so hopefully this photo is clear enough... Don't mind my finger, it's the only way it would stay open:



In theory they're color coded. If they're missing you'll just have to run one at a time or make sure you label the ends.

-Rog

[Rogviler]

Oh, and the diagram it refers to is just a schematic view of the same thing. If you want I can get a picture of that too, but the one I posted is just as accurate and is a better real-world view of it.

-Rog

[onlyaudis]

where does the "vacuum line from engine" originate, and what color is it? Could you post a a photo of it teeing off somewhere in the engine compartment? I fear the PO just blocked off the supply line to the system or hooked it up wrong.


The initial excitement has given way to reality now on this project, as the "things it needs" list just keeps getting longer and more involved. Dumped a ton of $$ on front end parts plus the Konis: control arms, ball joints, CV boots, tie rod ends. I think of myself as a fairly capable amateur mechanic, but did not want to try and tackle the front end on these cars by myself, so I rang up a nice full day shop California labor bill as well including a some misc. sorting out and the rear struts.


Needed to replace the brake master cylinder and proportioning valve, all 4 calipers needed rebuilding, new rotors, pads, and tires.

I just replaced the torn intake boot with a nice intact one, and now it is idling all over the place. everything is snugged up tight, so i can not understand what the hell is going on. Seems like everything I touch causes another problem right now. the brake reservoir cracked a fitting when I was trying to remove it to replace the M/C, and I have one of those on the way too-the 84 is unique and nearly impossibe to find.

Just replaced the broken drivers door mirror with a used one, and now I am not getting any power to either of the mirrors. left one worked before and I didn't even touch that one. the servo worked on the drivers side one before too, but the glass was loose. fuse isn't blown. Not getting power to the switch as far I can tell. maybe I bumped something in the door or under the dash while i was running the mirror wires.

I know I'll get through this phase of the mechanical sort out, but right now its a bit over whelming. think I will let the car sit for a few days and start fresh on it next week.

[Rogviler]

The line just comes off the back of the intake, right where there are all those hoses behind and under the air boot.

The line should be white:



The braided line goes up to this thing, if it helps you figure out which one it is:



Anyway, the white one goes through the firewall and over to the switch.

I would do a vacuum leak test. I've been convinced that the onle way to go is the "cheap cigar" method (or just light up a cigarette if you smoke). I connected a piece of hose to the spare port next to the brake booster line on the intake manifold (should be normally blocked off). Then just blow some smoke from a $1 cigar into it, with the engine off of course. You'll find leaks you never would have found otherwise. Much better than propane, which seems ridiculous by comparison.

You might just have some corrosion in the mirror connectors. It's pretty common since they're basically exposed to the elements inside the door. You'll just have to start cleaning connectors and checking continuity. Of course my mirrors haven't worked in years...

The nice thing is that once you replace everything you know it won't have to be done for awhile. It's like a whole new car.

-Rog

[onlyaudis]

Thanks. i found the line and it is stioll attached at least. when I can run the car again, I will do a vacuum test at the hose, and also at the switch itself in the console.

I think i found out what was going on with the idle. the 2 complicated shaped breather hoses that attach to the idle control valve are totally shot, and someone had just black duct taped them together. When I was moving things around to get at the air cleaner, must have lost the weak seal. just ordered those upgraded parts in silicone from 034 Motorsports, and should have them in a day or so. got a new mirror switch coming in too (was only $19 and is a likely culprit)






http://www.034motorsport.com/engine-...r-p-18018.html


http://www.034motorsport.com/engine-...q-p-18019.html

[onlyaudis]

finally got around to checking the vacuum lines, and I have no vacuum in any of the small lines. where exactly do they pull their engine vacuum from--so what is the source of vacuum for the small hoses (that go to the A/C system, the distributor, the dif locks) the small hole is plugged on the hose pictured right above this post--is that supposed to have something hooked up to it?

[onlyaudis]

got some detailed photos of where the vacuum lines should be hooked to from a fellow 4000Q owner--the PO wasn't even close on the vacuum line set up. had to totally redo the lines, and now everything works! A/C flapper, dif locks, awesome.