Passat Brakes - Beware

[passing]

If this refers to the vent underthe battery then I have seen that there was a recall in 07 (www.honestjohn.co.uk). But I have not had any notice from the dealer where I used to have mine serviced so I guess it is up to owners to chase them.

Apparently the VW fix is to remove the rubber vent/duct that causes the obstruction.

[Crasher]

According to our Audi dealer the recall is to poke out the drain bung with a piece of wire. If the bung is removed, fumes from under the car will be drawn into the heating system.

[Frank.A]

When I contacted my 2 local main agents with the recall number that was posted in a recent thread,I was told by 1 service manager that my passat was not included.He said the mod was to remove the grommets and that later passats did not have them fitted.
Even though mine had the grommets fitted (late 2002) he still insisted that my vehicle was not included in the recall.As I had removed them in 2003 it did not really matter but I reckon the car was not included because it does not have main dealer service history.
How VW can get away with this,especially since one of the problems caused is a braking issue,beats me.
There is a class legal action in the US on this design fault according to one of their websites.

Best,
Frank

[graham lawlor]

Hi just to say that my audi a4 2001 has the brake problems as above.So rang dealer to see about recall.They confirmed recall 2007.Will go through process of checking servo and hoses and report any costs to AUDI UK to see if any good will gestures can be sought.



Graham

[Silver surfer]

My car has this problem - exactly as you describe do you know how they checked servo ? this was caused by the plenum area flooding due to a blocked drain under battery.

HELP!!!! I HAVE A SIMILAR PROBLEM WITH MY BRAKES ON MY PASSAT. THE BRAKE PEDAL GOES SOLID AND THE BREAKS FAIL. ONLY SEEMS TO HAPPEN IN THE MORNING OF A COLD DAY (0 deg.) I TOOK THE CAR TO VW MAIN DEALERS WHO REPLACED THE SERVO PIPE. CAR IS STILL THE SAME AND RETURNED TO MAIN DEALER, WHO INSISTED THERE IS NOTHING WRONG.
I HAD ASKED THEM TO CHECK THE SEVO FOR WATER, WHEN THEY DID THEY FOUND I WAS CORRECT. THEY HAVE NOW QUOTED ME £600 FOR A NEW SERVO. DOES ANYONE KNOW IF IT IS POSSIBLE TO RECON THE SERVO, OR ANY OTHER WAY OF SOLVING THIS PROBLEM CHEAPER.

[Crasher]

The only way to check the servo for water and corrosion damage is to remove the master cylinder and look inside, which isn't easy without an endoscope.

[bg158a]

If I am correct the servo is basically a big diaphram with the master cylinder on one side. Can you confirm which side of the diaphram the water accumulates on. I am seeing these problems on my 51 plate passat TDI. Have had Vac pump and Vac hose changed but the problem now only seems to be their on mornings where the temperature is below around 2ºC. Like this morning. Complete servo failure on Motorway crawled in traffic for about 3 miles and just before the services the servo came back and all seems fins again.

Is it not possible to disconnect the vac hose and put in a small tube to try and suck out water. Just to tell if it is deffiently water in the servo.

Cheers Ben.

[Crasher]

The water gets in both sides eventually. The only way to tell is to remove the master cylinder or disconnect the servo pipe and use an endoscope!

[gribbo]

Another frustrated VW Owner. re all the above comments, same happened to my 51 plate 2.0 litre petrol estate. Bulkhead plugs blocked, bulkhead filled with water, Servo also filled with water then froze due to cold temperature, causing brake servo to fail so no brakes. When the brakes did work after a thaw on the up stroke of the brake pedal water was being drawn into the engine, as there is normally a vacuum on the servo, causing it to run like a bag of spanners.. gather that the comfort control panel is also knacked due to water ingress. I will be writing to VW UK to make a formal complaint about the brake problem as this could have killed not only me but other road users. I understand that their US counterparts have recalled all B5's for a safety check. May duplicate the letter to the watchdog tv programme and for auto express??

[pds999]

I've just started another topic on this but same has happened to my Audi A4 2002 this morning. Temp was zero and on way to town the brake pedal went hard and couldn't break. Crawled to nearest garage who said it is common with Passats to draw in water to the servo but he had not seen it on an A4. I've left the car there but have a feeling it's the same problem as it has done it a couple of times before on freezing mornings, but always righted itself immediately - today though it wouldn't sort itself and I had to pull into garage.

From some research I have done, problem seems to be one of following:

1. Servo and vacuum hose failure (pricey);

2. Vacuum hose from manifold collapsed in on itself and broken on metal pipe that comes upward from the manifold;

3. Water drawn into servo (caused by blocked plenum drain, etc). Need to remove master cylinder and check;

4. Vacuum hose crimped or split;

5. Vacuum hose too thin on older A4's - need a newer one that is reinforced and won't crimp;

6. When pressing the brake pedal twice quickly in succession, it can cause the brake to become hard. The brake hose goes through the engine compartment bulkhead and naturally passes through a grommet. When you press the brake the first time it causes the hose to “pull in” to the grommet (normal) but when you press the brake for the second time, the hose pulls in further and crimps thereby removing the servo assisted part of the brakes. Solution: change the grommet.