Have notice a few months back that the boot on my STi seemed to be letting in rain water in as some of the items in the boot are damp/wet, i initially though it was the build up of leafs and debris around the boot seal and cleaned that all up and just this last week with the heavy rain it still seems to be letting water in somewhere. I have done a visual check of the boot seal and its seems to be fine is this a common issue at all?

 

I had the same problem....I found that under the boot seal had corroded,water was running under the seal and dripping onto the carpet......I ended up cutting the corroded bit out and fabricating a new plate...

 

Mine leaks in too, i think its my rear window seal. My boot and rear lights are water tight and it took my a while to narrow it down but i think im there. I always park upbank now and get no water in.

 

Hi Lettuce, what year is your STi? The round foam mounting bolt gaskets underneath the spoiler can deteriorate over time letting water in.

 

remove the seal and apply some silicone along the lip and refit ,
the water sits in the channel and works its way under the seal.

 

NO!!!!

Do NOT use silicone, it cracks over time and you'll find it almost impossible to get the seal off again, should you ever need to.

This is the corrrect stuff: http://www.caravan-components.co.uk/...-in-400ml-Tube

To the OP:

Yes, boot leaks are common. There are main areas where leaks occur. I've had them all, but have had the car 20 years!

1. Rear lights. Most common, the rain water runs round the lip of the boot seal and over the lights, taking dirt and stuff into the sealant, which eventually gives up.
Cure: remove lights, clean out old sealant and bed lights into a 10mm bead of the above sealant NOT silicone, Tiger Seal etc.

2. Spoiler. Very common, same as above.
Cure: Remove spoiler, run bead of sealnt as above round bolt holes, wiring input hole and right round the base. reseat. wipe off excess sealant with white spirit.

3. Boot seal.
Cure: remove and run selant round, refit.

4. Air vents at base of wings, inside trim. Get blocked with debris and held open.
Cure: Clean out, ensure they close.

5. Rear windscreen seal. CAN go with time, usually shows itself by wetting the rear seat upright, rather than the boot.
Cure: you could buy windscreen sealnt and have a go, removal of all trim might show where the sealant has gone. Alternately, pay a professional to remove and refit the rear screen.

HTH.

 

funny that,as never did on mine after 5 years of use and still running this way after a further 3 years after been sold:

general purpose silicone dont crack

 

Aye, it does. It's not meant for the movement you get in a vehicle. Plus it makes the component it's trying to seal all but impossible to remove, and a right pita to clean up if you do get it off.

But hey, your car, your choice.

 

its 2004

 

I'll try number 3 first as thats the easiest

I dont think its the rear lights thats the issue as the damp/wet areas seems to be kind of running horizontally in the middle of the boot.....which would possible also rule out the spoiler but then we all know water has a mind of its own and can travel.

That said i did need a completely new rear window about 3 years ago so maybe that wasn't sealed correctly

thanks for the suggestions thus far

 

There will be a dozen or so nuts to undo inside the boot, 2 are hidden behind rubber bump stops towards the ends of the lid which just pull off/push in. You will also need to disconnect the brake light on the right hand side attached to the boot lid arm.

Spoiler just lifts off, it will pop out of the 2 locating press clips on the lid as you lift it. Brake light cable might need a Wiggle as it finds its way through the hole. Easily done yourself, just be aware that it probably weighs about 20kg.

Worth pulling the spoiler off whatever you do as I guarantee the aftual spoiler gaskets are shot. Spoiler then rubs the paint off the boot lid causing rust underneath it.

Regards, Sam

 

Oh the factory torque value for the nuts is something like 8lbs/ft. Only nip them, if you think about giving them any kind of grunt they will sheer the studs.

 

Could be the glass if its been replaced ..............

Try running coloured water (use food dye) over rear window, seal boot seams with tape.

you can use this method to the main areas prone to leak.....rule each one out as you go around.

Good luck.......

 

My suspicion is now the rear window.

 

Could well be it does seem to make a sort of cracking noise when its super cold in the mornings and i reverse of the drive for whatever reason.

Is it best to call Autoglass out or is there a better alternative?

 

If you remove the rear trim and parcel shelf, you ought to be able to see under the glass where it's sealed...or isn't. On mine I could clearly see a drop forming inside every ten seconds. Doesn't take much to wet the inside in a rain storm. I had no idea until I reached across the back seat and it was damp. The interior did get steamed up and there was condensation inside on cold mornings, but no aircon, so???

You COULD try some Sika flex under the edge? Or just bite the bullet and have it removed, cleaned and resealed.

However.
It's not cheap to have done, so do make sure it's that and not one of the others before spending £££

 

Ok going to clean up the boot seal and add sealant, i got the Carafax IDL 99 Cream Mastic Sealant alcazar recommend above.

Quick question, am i wanting to apply the sealant to the inside of the boot seal and then reapply the seal or place the sealant on the top edge of the lip on the bodywork (that the boot seal goes over/clips on to?

Im not so sure it is the window leaking as the rear parcel shelf is never damp to the touch at all and have never see any condensation on the rear window

 

I removed my boot seal, cleaned up and applied carafax to the metal lip, then replaced it.

 

Any progress Lettuce..?

 

Ok removed, cleaned, applied and replaced.

There was a fair amount of debris under the seal itself so that wasnt helping the issue, guess ill wait and see if it leaks again

 

What have you done with/about all the other possibles?

 

Best to do one at a time, so you know you have found the culprit.

 

I suppose.
In my case, the boot seal was way down the list. It did go eventually, but not before the lights and spoiler had done their worst, LOL