All-Audi-Home

10/31/13
I found, like others, that the changeover valve (intake manifold flaps) had frozen on the D2 4.2 engine. One vacuum actuator was broken (bolt separated from the dashpot). I followed meticulous detailed directions given by others (Thanks PaulW) and disassembled the linkage and the front seals at the manifolds.

See> http://forums.quattroworld.com/a8/msgs/44689.phtml

Once the flaps were freed up and reassembled I move to the linkage. I tried repeatedly to repair the vacuum actuator but the epoxy simply could not stand up to the temps and it failed. Knowing the Audi prices ($400 each side) I went for the Lamborgini part ($136.64 including S/H)( lambostuff.com ), and I can confirm it is the same part with the Audi part number on it.

With the new vacuum actuator installed the next failure was the arm which would no longer hold against the spring. Back to the drawing board. I did not want to pop for the Gruven billets so I searched the World for German carburetor linkage that used the same size ball (8mm) as the linkage arms on the Audi. I found that early Porsche, VW and Volvos all used that 8mm ball linkage, and all had the tie rod ends that can be separated from the ball. Separation is a necessity in this case as the ***** are molded into the Audi linkage arms and cannot be removed non-destructively.

I found a set of 4 M5 tie rod ends for the 60s era Volvo 122 series on eBay in Athens, Greece that are perfect and exact matches to the old German & Swedish parts. This link may still show what I found.

http://www.ebay.com/itm/231073067193...S:3160&vxp=mtr

I found some M5 threaded rod to tie the tie rods together and added locking nuts to finish the job. If you're looking for this I purchased from the Boltstore on eBay. Came out quite nicely. This URL may still work.

http://stores.ebay.co.uk/Boltstore

Total job expense $172.94 including S/H in 2013 dollars. See the pix of the job. Note that the first pix shows the old actuator and the second the new one. The whole job looks quite nice.

Roland

crispy222

So the actuator is:
077907327A DIAPHRAGM, ACTUATOR
correct?

Razman

Thanks for posting this. I just found a new project for my '00 D2, as both are stuck in the 'engine on' position! I guess this means I'll get more top end torque from it when done? Cool...

Raz

silverd2

You're welcome

All-Audi-Home

Yes, we used to call those dashpots, but that name seems to have disappeared. That exact part is used by Audi, VW, Lamborgini, and Rover that we know of.
Roland

Razman

So the other day I sprayed the actuators with some Teflon lube and they have since freed up a bit. I am now able to manipulate them manually and they are about 80% better than before. Just a small amount of sticking at the limit of travel.

So I doused them again with some more lube and tested them by having someone start the car and rev the engine. Third stage flaps work as designed but the second stage is not opening up. Possible solenoid issue? I'm going to check it; any other thoughts would be appreciated.

While we're on the subject of vacuum lines and such, anyone know what that thing is for under the lip at the bottom of the windshield on the passenger side? It has a wire going to it and a long (1.25"?) tapered, white fitting (for a hose) on the end of it pointing towards the driver's side. I can't find the remnant of any hose there. It can be seen if you look above the box containing all the computer modules and under the lip where the rubber strip is (just below the vents that are directly under the windshield). It's about where the passenger would be looking through the windshield (in location relative to the side of the vehicle).

Thanks,

Raz

Razman

Pulled the vacuum lines off the solenoid, let some Teflon lube soak in there, pushed down through the fitting with an allen wrench to break it free and now I have normal operation throughout the rev range.

Only thing is I won't be able to tell until Wednesday morning when I go in to work - wife is taking the car tomorrow and I'm taking hers. I wonder if she'll be able to tell that I used Vag-com to put the transmission in sport mode...

Raz

S8ilver

I could change the color of my interior and I don't think my wife would notice

Razman

Mine definitely would and ask where I got the $$ to do that! You should have seen the look on her face when I told her I could use the Vag-com cable to add another 150 hp...