Steps to remove G291 Sensor (air suspension)

[seninha]

Hope someone can help me to figure out what steps I need to follow to do change the G291 Sensor.

Due to the fact that my Air suspesion stay on MANUAL , and only drops the car automatically I did a VACOM run and it gave me an error on the G291 valve.
Did some reading and already follewed the next steps:
-checked all cornes by spraing water/soap to find any leaks. Result: NONE
-checked all lines for leaks.Result=NONE

Now I was able to get a second hand G291 Sensor, and I would like to install this one to find out if this will solves the problem.

But before I do this , I would like to know what to do before I can unplug all the airlines.
Do I need to rise the car to jack possition?
And will th eair com out when I unplug the valve?

Here is a picture of the sensor:



and where you can find it under the car:

[julex]

Valve block is the module that directs air around the lines and bags. Once you remove air lines, you will effectively open the system and all corners will sag super fast. This is possibly very dangerous so ensure that you are at the very least on ramps when this happens so that you don't get crushed underneath. There is almost no ground clearance once the car hits bottom.

If using jacks (use ramps!)... use special precaution. Since the car will move when sagging, there is a danger of jack losing its grip and stands topping over.

Put the car in level 1 before you disconnect the valves since this will ensure the suspension will travel the least distance towards bottoming out.


Good luck

[seninha]

Thanks jules.

My idea was to lift the car in a garage (I can rent the lift by the hour).
Already thought that all the air would come out when I disconnected the lines,but now I know for sure it will.

[Hugh@EuropaParts]

If that doesn't work ** the compressor may be on it's way out. I hate to link elsewhere, but this might be useful ..

LINK TO: G291 code seems to be gone after compressor replacement

[seninha]

I dont really think that the compressor is giving this error.reason to think is the fact that when I rise the car by using the control buttons, this works normal.
Car goes to the next level without any problem.

Also , the pump builds enough pressure. (controled this while driving using VAG-COM)

[seninha]

OK,weekend is almost heren I am finally going to remove the G291 valve.
But before I start this job I need to know one more thing.

After I remove the old valve and place the new one back,DO I NEED TO CALIBRATE the suspencion?
Or will it rais to normal hight as usuall?

[pzi123]

I think i have a faulty G291 or 'valve unit'. When I do output tests with VAG i hear clicks when trying to level each corner but nothing happens.
I googled for the part numbers for the 'valve unit' which is audi 4F0-616-007-A or original ATE 5-1524-0005.2 but all I get is some crazy prices or German ebay.
Where do I buy that?