Not another leak!

[GemGTI]

Had a major leak to the offside rear footwell in May last year. Coming up through carpet, the mat ontop was dry. When I had my car re trimmed, the guy said it was the doorcard which was letting it in. He sorted it out and since then every time it had rained it had stayed dry. Last night it p!ssed it down and this morning the offside rear footwell was like a mini paddling pool! But again the mat ontop of the carpet is dry! Beats me! Anyone else have any ideas? 

Gem

[richandhazel]

O/S rear light cluster leaking? Were you parked facing downhill? Could be tracking through from the rear light cluster down behind the rear seat and into the footwell.

I assume the front footwell is as dry as a bone?

[GemGTI]

I was facing slightly up hill but only slightly. I wouldn't say the front footwell was dry as a bone, somtimes there is a slight trickle coming from behind the peddals but I assume this is a seperate leak as the trickle never seems to reach into the rear footwell? Ive checked those drainage holes under the bonnet and they are clear. Just seems strange that the mat is always dry but the carpet is soaked!?

Gem

[richandhazel]

You have some strengthening channels running fore and aft along the floor pan. The water can leak in, settle into the channel and then track and collect somewhere completely different. 

This pic from underneath gives you a pretty good idea what I mean:-

[GemGTI]

Any idea how I find out if that is what it is? Or how I would go about sorting it out? (Not very clued up on technical aspects of cars!)

Cheers,
Gem

[Phil303]

I had the same problem and it drove me mad trying to find the problem.

Following on from richhazel's reply, chances are the water is building up in the scuttle (the area below the windscreen where your wiper motor sits). If the drainage holes on either side are blocked the water will rise to a level until it finds some way of working it's way into the cabin. Even though the drainage holes appear to be clear as you say, bear in mind the scuttle area is not 100% watertight so the slightest gap will be enough for the water to escape. It will run down these channels *under* the front carpets where it then gathers in a pool in the rear, soaking it from the underside, which is why the front carpets and the mat on top in the rear stays dry. Clever bit of design!

Peel back your front carpets and you'll see these channels. Be warned - it may smell! Recheck your door seals and make sure the door drainage holes on the bottom of the doors are clear, but I'd bet that the main culprit is the scuttle. I've since sprayed and sealed my scuttle so it shouldn't reoccur. It's a good idea to check the drainage points regularly though, especially in winter with leafs and cr*p flying about. Hope this helps.

[GemGTI]

Thanks Phil, how do I get to the scuttle to see if this is the problem?

[Phil303]

Open the bonnet and at the back of the engine under the windscreen you should see a black plastic moulded tray covering the wiper motor and wiper mechanism.

Unclip this tray and you will know be looking at the scuttle! Have a poke around and clear the drainage holes. You are looking for any major and minor signs of cracks or places where water can run in. Best thing is to clean it out thoroughly and give it a new coating of paint or sealant of some description. I'll try and find out what was used on mine and post it up here.

[richandhazel]

It is also well worth checking all your cable grommets are in place i.e speedo cable, accelerator cable (may explain your leak around the pedals which may well be the same leak believe it or not) etc.

[GemGTI]

Thanks guys your help is greatly appreciated!