rear diff controller .. audi s2 avant vaccum

[S2_avant 19930325]

Which of the 2 vaccumlines goes on what intake on the diff acctuator.?
Yellow and blue line?

I mean the plastic part the like an accutator. 20210212_152002.jpg




vaccum lines.jpg
If i look here. I have a standalone ECU , so think pink line i do not use.
I dont have a A/C ,, so i should have 1 "pink" line from intake the check valve ( where is its location? )
The vaccum rerservoir is what exactly ?
And the rear diff controller is what ( where is it ? )
As i read the picture .. the blue and yellow vaccum line on the first picture is coming from the rear diff controller correct ?

[newsh]

In coupe the check valve and diff controller are under the rear bench. I believe the Avant is the same?

[larsaskogstad]

I think you can just check and try it out, if you connect it wrong you will open the diff instead of closing it when you push the "Lock Diff" .
Then just swap around.

[S2_avant 19930325]

Hi ,, just made a little film on how my lines are connected ,,, it does not look like in the film i did....

https://www.youtube.com/watch?v=0abN...b_channel=LjTo

The green line for the ECU i dont have/need , i have standalone ECU with another vaccum line.

I dont have AC on the car.

Where is the vaccum reservoir ?

The blue/white line has been cut at the controller , why do you think and what does that cabel do ?

[ericd]

It's a long time since i've looked at this stuff , but I'd say that the blue/white line is tied to speed and supposed to disable diff at "x", cutting this wire if i'm remembering correctly would mean you could still have diff engaged at speeds above whatever "x" was supposed to be , potentially dangerous but i'm sure it had been done/tried a few times with various results.

apologies in advance if the above is incorrect , but ther's something familiar about the blue/white wire, somebody will know ...

[mdz]

White/blue wire is vehicle speed signal line. If you cut it, difflock control unit does not see moving speed and does not know when to disengage lock so keeps it locked until you switch it off manually.

[S2_avant 19930325]

so when i get the car on the road , the diff will be activated all time , so i have to reconect it back if i want the car to act normal. correct ?

[newsh]

so when i get the car on the road , the diff will be activated all time , so i have to reconect it back if i want the car to act normal. correct ?

No it will just switch on or off with the switch and not switch off automatically above 10 mph ( or whatever it it is)

[S2_avant 19930325]

When im driving on the parking lot the diff on the car is activated all the time ... is there anyway to diactivate it manually ? Cant drive faster , have to tune it first.
Dont want to have the diff activated at the tuner ,,, he have hub dyno. When i press the diff button it lights. I dont know what the former owner have done with the diff. I dont have the time to check if the vaccum lines are connected in the routing. On the film , can i just draw a vaccumline to the manifold and connect the cut wire ?

[S2_avant 19930325]

My speedometer does not work so it will not know what speed it is. So the only thing is to disconnect it manually. How ?

[Bowie69]

Pull off the vacuum lines, in fact if you are struggling to deactivate it, you likely have them on the wrong way round on the diff actuator (ask me how I know) meaning on is off and off is on!

A quick crawl under and re-plug and all will be sorted.

And yes, if speedo not working, it won't disable the difflock automatically at 8mph.

[larsaskogstad]

By memory I think the yelliw is closest to the driver side of the car (lhd)

[Bowie69]

By memory I think the yelliw is closest to the driver side of the car (lhd)

That's fine if you haven't disconnected them under the rear seat as well

I had for cleaning purposes, hence I got them wrong when plumbing back in.

[S2_avant 19930325]

But cant i just blow with air and compressor .. directly on the accuator ? what does the accuator diff and not diff ? Is the vaccum that activates it or vaccum that deactivate it ?Hmm can i move tha arm onthe acuator with my hand and lock it like that with a strap ? Trying to make a easy solution .. i dont have the possiblility to check the hole vaccum harnes for it . And the sppedometer does not work , so it will still not work even if i connect everything correct.

[S2_avant 19930325]

So if understand that correct , i just have to look the arm in the diff to be fixed then it will be ok ... correct ?