Technical Cabin air condensing in the sills?

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Technical Cabin air condensing in the sills?

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I am posting this in the Panda section because I know some of you take your Pandas seriously and want to keep them for a long time. I have a 2004 Punto which seems to have a similar construction? I was surprised today after I had driven about 15km round trip in -5C on snow covered roads and had the car in the garage and jacked it up onto jack stands, that there was water dripping from both sills through the sill drain holes and from some of the sill plastic plugs. The whole of the bottom of the car was otherwise completely dry. The wheel arches had melting snow. I have plastic splash guards front and back. I am assuming this is no connection between the wet wheel arches and the wet sills. Each end of the sills looked totally dry inside the plastic guards. I have recently repaired small rust holes in the rear wheel arches and I have had a look inside the sills where there is a considerable amount of rust on the bottom of the outer sill in the rear half of the sills. The front part of the sills appears to be in good condition. The car is kept in a dry garage so I am assuming this corrosion is being caused by condensation.

So what to do about this? I know there are a few ways the pressurised warm humid cabin air can reach the sills. There are a few small openings front and back and then in the middle the door pillar has this plastic bag under the seat belt mechanism with foam in it and there are some air gaps there. There is a sill inspection hole? in the rear passenger area on both sides - I am assuming that was put there by the factory.

I have not recently checked that air opening valve thing behind the rear bumper.

I suppose it makes sense that a small amount of water will always be getting into the sills and condensing in cold weather when the cabin air is warm and I am breathing. The windows however were not fogging. The car has snow 'buckets' for your feet front and rear. There is no rust at all under the carpets or anywhere on the underside of the car other than at the sills, the rear bumper brackets and the rear subframe under the springs.

Has anybody here experienced this before?

Edit: I suppose i can test this by putting a tube in the sill and seeing what happens to the inside of a glass jar that is outside the car. It must fog up to some extent. Just recently I went into an underground shopping car park and it took me a while to realise the *outside* of the windows had very quickly totally fogged up.
 
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short answer I dont know


I believe but not 100% sure water can enter the sills from inside the front wheel arches behind the plastic covers

annoying I have out many times but never payed attention rearwards. Front definitely is open past the headlight.
 
the front of the sill is closed, spot welded to the frame and seam sealed. the rear is welded to the inner wheel tub and again sealed. But the A, B and C pilar are connected to the sill. so water that comes into one of these will flow down to the sill and go out using the drain hole. So a bad window rubber, a leaky sunroof or a pinhole in the sealer will result into water there. That is the reason there are drain holes in it.
 
The door skins have quite large drain slots at the bottom. The sills also have drain slots. The cabin air intake has rubber drains on the bottom edge. It's all about keeping water out.

If you are concerned about internal corrosion, get yourself some replacement rubber bungs and an endoscope so you can take a look inside.
eBay number 154557786016 is one of many. Fit the replacement bungs with red rubber grease so they don't get damaged on the way in.
 
Don’t think you’d get enough condensation from inside the cab unless your using the panda as a mobile sauna
🤣



Here is my panda theory...

If I move my newer 57 plate Panda off the drive to get in my garage the car gets parked with front end slightly raised where as the drive is level...

Back in Summer & after a long dry spell with little chance of me washing the panda I spotted a wet patch just in front of my Panda's rear wheel when I'd accessed the garage. Thought a cat had peed on my car. Few days later I happened to notice the same thing & spotted a drip from the sill... Few My panda isn't being targeted by the local Tomcat when it moves into its territory.

It seems to happen every time I move the car so I recon the Panda won't fulley drain any leak into the sill if parked on the level so it's a water trap.

Makes me wonder if that's why the other side needed welding for the previous owner.

Plenty of posts about Wet Sills over on Alfaowner:-


I think I read that thread a fair few months ago seem to remember reading sills are either wet or dry construction.

Leaks on dry sills cause the car rusts from inside out, so those in the know check their Alfa for wet in the sill / look before buying.

Think someone mentioned that the Punto also suffer from this faulty construction, why not Panda too? Probably a bit late to claim warrantee for most Panda in the MK3 section.

By contrast my previous 2006 panda sporting at 197K had solid sills (shell was really good) & I never saw this drip when I moved it to access the garage.

Can't say I've checked where the water is getting in as it was a stop gap Panda & didn't expect to keep it so long :)
 
Don’t think you’d get enough condensation from inside the cab unless your using the panda as a mobile sauna
🤣



Here is my panda theory...

If I move my newer 57 plate Panda off the drive to get in my garage the car gets parked with front end slightly raised where as the drive is level...

Back in Summer & after a long dry spell with little chance of me washing the panda I spotted a wet patch just in front of my Panda's rear wheel when I'd accessed the garage. Thought a cat had peed on my car. Few days later I happened to notice the same thing & spotted a drip from the sill... Few My panda isn't being targeted by the local Tomcat when it moves into its territory.

It seems to happen every time I move the car so I recon the Panda won't fulley drain any leak into the sill if parked on the level so it's a water trap.

Makes me wonder if that's why the other side needed welding for the previous owner.

Plenty of posts about Wet Sills over on Alfaowner:-


I think I read that thread a fair few months ago seem to remember reading sills are either wet or dry construction.

Leaks on dry sills cause the car rusts from inside out, so those in the know check their Alfa for wet in the sill / look before buying.

Think someone mentioned that the Punto also suffer from this faulty construction, why not Panda too? Probably a bit late to claim warrantee for most Panda in the MK3 section.

By contrast my previous 2006 panda sporting at 197K had solid sills (shell was really good) & I never saw this drip when I moved it to access the garage.

Can't say I've checked where the water is getting in as it was a stop gap Panda & didn't expect to keep it so long :)
Thanks for this information. My car is a punto. I posted here on the basis panda owners seem to be more motivated to keep their cars longer and might have found solutions. Thanks again!
 
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The door skins have quite large drain slots at the bottom. The sills also have drain slots. The cabin air intake has rubber drains on the bottom edge. It's all about keeping water out.

If you are concerned about internal corrosion, get yourself some replacement rubber bungs and an endoscope so you can take a look inside.
eBay number 154557786016 is one of many. Fit the replacement bungs with red rubber grease so they don't get damaged on the way in.
Please can someone point out approximately whereabouts the drain slots mentioned here are positioned along the sills? Are the slots actually in the sill seams? Thank you
 
Please can someone point out approximately whereabouts the drain slots mentioned here are positioned along the sills? Are the slots actually in the sill seams? Thank you
As far as I know there aren't any

Some builds have rubber bungs plugging holes along the bottom, some dont
 
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