omarcarbomb

I finally bought the D2 A8/S8 Bentley Manual because I needed details on replacing my heater control valve.

The instructions on how to do so are miles away from what is actually involved.
There is no way to get the job done using this manual.

Has anyone used Bentley to do finish remove and re-install of heater control valve job?

I feel ripped off.

silverd2

Have never had the need to pull the pump/valve unit, but have read the procedure.

What is or is not happening?

omarcarbomb

I think you know enough about the car to look at the manual yourself and see that there is no way to get to the valve with the info there.

The cabin air intake box is pratically built into the car and is not coming out with the limited instructions - not even close. Perhaps you could remove the master brake cylender and pull valve out to the side but you still probably wouldn't be able to access the hoses that run under that front lip of the air intake toward the ECU/TCU.

The lower part of the intake box is one piece and goes all the way down around the heater core. The bentley manual make it look like it comes out with 4 bolts but it has hoses going into the rear of it and as I mentioned before it it dug deep into the engine compartment wrapping down so far that there apears to be no imaginable way to remove it without taking the dash apart.

I would love to be proved wrong on this...
It wold be nice to know the manual was golden.

nyrobbie77

I had to replace the pump when I first got my A8. Someone put the wrong coolant in and it jelled up inside the pump causing no flow through the heater cores. Flow through the cores was clear, just nothing through the pumps.

I removed the brake master cylinder and booster to get access to it. You CAN reach the hose clamps on the passenger side to undo the hoses to the passenger heater core. You do not need to remove the cabin air intake box or hack it up as some people do.

Here is a link to my thread on replacing the unit:
https://www.audiworld.com/forums/a8-...-heat-2818957/

omarcarbomb

thank you for the reality check. At least I'm not left wondering if there is something I'm not getting about the manual. It looks like removing the brake cylinder is the logical course of action.
It is weird that I put off buying the "the manual" for 5 years and bummed info online and finally bought it for a procedure that is not included.

Karma?

silverd2

Now I'm confused. My Bentley describes the procedure just like nyrobbie77 described his successful swap.

Removing the brake booster is in the first few lines of the instructions ... and nothing about removing the air intake box ... just the top cover w/flaps.

omarcarbomb

thanks for taking the time


I will look again

you got a page number?