Dreaded water leak

There should be water drain holes on the bottom inside of each door panel, make sure they are not blocked by rust proofing gunk or dust.

Correct.
The ac runs in defrost mode to help dry the air blowing on the windshield. The cabin has too much moisture in the air.
You need fresh outside air and it needs to be dried by the ac to work correctly. So if the cabin air filter is dirty you would not get enough fresh air.

If battery leak it is not water but battery acid. If water then there must be leak into trunk.

Hi Darren

most often the cause for this is dirt in the jets, get a pin or a needle and poke the needle into the holes on the washer jets, this should clean and dirt out. hope this helps
Regards

Dan

There is a small drain plug that needs to be removed, the car level, suspended on Jack's, monitor the tranny fluid temperature with obd2 tool, engine started from cold, , the fluid will ooze out of the open plug hole at proper temperature. Use a new plug when done topping the fluid. Intricate task

all sunroofs have drain pipes, usualy 4, one on each corner, they usualy run down the A pillars at the front and poke out near the kick panals by the footwell. the rears often run down the C pillar to the vicinity of the boot.
open the sunroof up and carefully pour lots of water around the drain gulley of the sunroof, you should see it pissing out onto the floor at the front and rear on each side. make sure water goes down all 4 corners of the sunroof and check. Pipes can come of at the roof. also the drain grommets block up.

common problem on passats also is the pollen filter housing letting in water (under the scuttle panel beneath the bonnet. on left hand drives though, this fills the passenger side only (left). not sure on RHD which side pollen filter housing is on , but when they leak the water fills up inside the car on one side only, which can flow front or rear depending on car being parked up or down hill.
the seal between the pollen filter housing and the bulkhead often leak, if you press down on the plastic housing you may hear the seal squelching water. there was a recall on this, so it may have been done.
If the comparment under the panel (where the battery is) is filling with water, there is a drain grommet under the batter that also blocks up sometimes, causing it to fill up and flow in where it shouldnt.

Hi

Common fault with VW's firstly check the door seal at the bottom and make sure it is not wet inside.

Next place is under the bonnet, just under the windscreen below the wipers you will see a long tray the "skuttle panel" leafs and muck build up in here where the drain plugs are once they get blocked the water starts coming in the car from behind the dash board. You should be able to see the problem visibly and it should be easy to clean.

I had this on a golf about 2mths ago, and a polo a while ago and also on a few passats.

Regards

Dan

My 2001 passat did the same thing. my leak was coming from the door panel. Open your door and use a water hose to simulate rain water running against your window. Water should run into door and drain out of several drain holes at the very bottom of your door. Check for water leaking from the bottom of your plastic door panel. The water runs down into the door and leaks through your inner door panel seal causing water to leak inside from the bottom of your door panel and run into the floorboard instead of draining out the water hole in the bottom of your door.

On the bottom of the diesel filter...a plastic bolt.

Hi,
This is the second Vw I have responded to in a fortnight.
Your lack of power I presume always happens when the glow plug light illuminates?
This is because it is causing over combustion to vaporised diesel, I would be looking in the Glow plug timer and relay, as for Turbo lag, I run a E34 6 cyl Bmw Diesel and the Turbo only kicks in around 2,500ish so maybe yours is a little tired or in need of a check up?
Hope this helped,
Paul 'W'
Onyer~EDson(:0) {#><U.K.
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