Secret factory feature: Fish pond in the boot

[minke]

Funny you mention that - my friends Mk5 GTI (which he has since sold) had an issue where water would get into the cabin whenever it rained or he washed the car. We thought it would be the sunroof but could never pinpoint exactly where the issue came from. A while after this was discovered, his ECU died out of the blue one day after he washed the car.......i bet this is what happened.

Yea. the ECU is in the footwell on drivers side.

[Guest001]

I have same issue but car was in a rear ender. Sometimes tail light fills with water too. After that i got ponds, before that no ponds.

Take it back and make them fix it properly If it was an insurance job get onto them as most guarantee repairs for life

[Lucas_R]

Yea. the ECU is in the footwell on drivers side.

No its under the plastic windscreen cowl (on the Mk5 GTI and Mk6 GTI/R anyway) near the windscreen wipers. Other models might have them in the footwell.

[minke]

No its under the plastic windscreen cowl (on the Mk5 GTI and Mk6 GTI/R anyway) near the windscreen wipers. Other models might have them in the footwell.

There's some body control module in the drivers side footwell that got wet and made the car a brick.

[duck]

Take it back and make them fix it properly If it was an insurance job get onto them as most guarantee repairs for life

You're right mate. Good point

[Lucas_R]

There's some body control module in the drivers side footwell that got wet and made the car a brick.

Yes there are plenty of electronics under the dash and near footwell's you wouldn't want getting wet, but the main engine ECU is under the windscreen wiper cowl. I guess damage to any of these would render the vehicle useless.

[jets]

but the main engine ECU is under the windscreen wiper cowl.

A Mk2 GTI that was my previous car also had the ECU in that position & one day I was fiddling around & spotted water laying around it.
It turned out the drain tube/tubes were blocked with rotting leaves. After that experience I am pedantic about removing any leaves going for a ride not just my car but any visitors as well.

[Mk R]

So it looks like the metal frame around the vent was damaged at some stage and this was the result. You can see the two streams have been running for some time. The one on the right looks like it's hosting new forms of life.

Bumper is coming off today in the sunshine and i've got two tubes of windscreen Adhesive ready to go. Going to giver both barrels and then clean out the boot seal which seems to have accumulated several years worth of sandy dusty slime under it over the years. Will put up some more pics when the job's done.

[Mk R]

In anticipation of yesterdays torrential rain I had the mechanic silicone the vents while they were doing a service. Didn't work out so well and there were still a few leaks but nothing like the pool of water i had previously. The left side vent was on backorder and i didnt want to do this twice so i decided to repair both myself. There's also a whole lot more rain coming so I wanted to get on top of this gremlin ASAP.

Today I had a few hours up my sleeve so off came the bumper (apologies if it's sideways, the file shows the correct orientation):


From there it was a look at the patch job and figuring out the root cause of the issue:


Both vents turned out to have already had the bottom clips snapped off. This meant there was no compression on the rubber ring and no seal. This shot shows the snapped bottom clips. Was identical on both sides. These vents need to be removed top first if anyone finds them self doing this in the future.


Next the existing silicone was removed from the seal area. This was an unexpected pain in the a$$. I ended up using an Opal card to scrape most of it off. Seriously regretted having the patch job done at this point.


As the bottom of the clips had been snapped off, i needed something to hold the vent in place with a nice seal while the Sikaflex 227 did its thing over the next few days. I ended up drilling a small hole in the vent plastic on the inside and using some plastic cable ties which hooked up nicely to a random hole in the chassis.

[Mk R]

I then gave the surface a wipe down and went completely overboard with the Sikaflex. It looks like a dogs breakfast but it'll hold nicely now.

[Guest001]

So the question is why were the bottom clips broken. Had it had a prang and the panelbeater cheapskated. For future reference turps removes silicone Scrape as much as posssible off and then wipe rest with a soaked turps rag till its all gone. Adhesives dont stick to old silicone very well.

[Mk R]

So the question is why were the bottom clips broken. Had it had a prang and the panelbeater cheapskated. For future reference turps removes silicone Scrape as much as posssible off and then wipe rest with a soaked turps rag till its all gone. Adhesives dont stick to old silicone very well.

Thanks, that's good advice. After 20 minutes of scraping I ended up soaking a hand towel in turps to scrub it clean before laying the fresh sealant on.

[Guest001]

Thanks, that's good advice. After 20 minutes of scraping I ended up soaking a hand towel in turps to scrub it clean before laying the fresh sealant on.

Very good hope it sticks as Sikaflex is a far better product than Silicone. I used to be a roofer in a past life and never used the stuff as with dissimilar materials silicone always pulls off one of them if there is movement or even vibration The correct Sikaflex stays stuck.

[Transporter]

So the question is why were the bottom clips broken. Had it had a prang and the panelbeater cheapskated.

It certainly looks like that, or it was damaged in transport and someone did a quick fix.

[Mk R]

So after a weekend of rain the vents and boot are completely dry. The boot seat was removed and all the gunk cleaned out and replaced. Only thing left to do is to tighten what i'd call the boot bump stop above the left rear light assembly which has a little play and steel brush away some of the surface rust this leak has caused.

Taking the rear bumper off with the bluetooth music playing for a few hours killed the 4 year old battery so this leak fix has now turned into an AGM battery install project