waterleak from dash into passenger footwell

[mr.220cdi]

:arrow:hello fellow merc drivers,just bought a 1999 c class 220cdi,drives great,few rust spots here and there,however was detailing the interior of the car today and noticed water leaking onto the n/s/f floormat when i moved the car to vacuum that side,it* only seemed to appear when i moved it and it was sitting on a slight uphill gradiant,having been a former bmw technician(20 years ago)and having left the trade around 10 years ago i would be a bit rusty myself,could it be the heater matrix,something to do with the aircon,or hopefully just a blocked drainage hole and pollen filters,previous owner did have car parked under trees and we have had alot of rain here in londonderry these \last few days,however when i removed the floormat the carpet was quite sodden,it smelled odourless and tasted of water-any sugguestions comrades

 

[lordluvitt]

Sounds like blocked drainage holes. Exactly the same thing happened to my 1998 C180. The drain holes are easily got at. There is a central one beneath the windscreen wiper - assuming you have the single wiper - and you'll need to remove the plastic trim at the base of the windscreen to get at this. It is this central one that is likey to be the main culprit for the water in the footwell.

Another drain hole can be found on each side of the windscreen on the inside of the inner wings (on the nearside this is down by the front of the ECU on mine). These feed into tubes that run behind the plastic trim inside the wheel arch which discharge to the road beneath. I found on mine that there were leaves and muck trapped behind the wheel arch trim which had led to the blockage of the pipes.

Its not a long job to clear the blockages but messy. Leaves and seeds falling from trees are the likely cause of the blockages. Fortunately this job costs nothing to do unlike repairing the heater and aircon!

 

[television]

As above the heater air intake box need the drains clearing

 

[mr.220cdi]

thank you for the advice,will attempt to clear drainholes tomorrow,looking through service receipts and found that the windscreen was replaced on vehicle in april this year by autoglass,if not drainholes could this be a possibility also?what do you use to clean out the holes?my mate has a compressor, blow air would be a good one i am hoping that its not something major and am annoyed i didnt see it when buying the car-rose coloured glasses

 

[television]

Strimmer cord is good and cannot damage any pipes

 

[Iain the gadget]

Strimmer cord is good and cannot damage any pipes

Same thing happened on my W202.
Exactly as above, clear the centre drain of debris and your problem should go away. The bulkhead acts as a reservoir when blocked and the first exit point is the air intake above the heater fan.

Good Luck!

 

[lordluvitt]

I seems to remember that I just had to handpick the debris from the top section of the hole and then I gently flushed it out with clean water. If the blockage is more severe then poke about with something sturdy but take great care not to cause damage.