So as you know I have had an issue with water ingress into my mk3 Ford Focus and I thought I had fixed the issue. Turns out I was utterly wrong.
Water was still coming into my car. I started by checking some of the other rubber grommits under the rear of my bumper. Suddenly I was greeted with dripping water on my face and arm.
I knew at this moment that the issue was definitely the vents. I followed a very handy video I found on YouTube that showed you step by step how to remove the bumper.
The only difference I found between my car and the video is that my car had a few extra screws (3 on each side instead of 1 shown in the video) behind the rear wheels to remove the bumper.
Once the bumper and rear light clusters were removed I was then able to check the vents. Low and behold they were indeed loose and the cavity behind them was full of water.
I had previously found a video that someone had uploaded to YouTube which explains how to remove the rear vents. He also explains how to seal it all up. I followed this guide quite closely making sure I over did all of the sealing. It’s messy, but I can’t say I really care as I just want water to stop getting into the car and ruining the upholstery.
I removed the sound dampening material from the vents and I was able to squeeze out about a litre of water combined from both sides. I then cleaned and dried the insides and all around the vents themselves to remove any left over residue, so I was able to make a nice and clean seal.
I then went ham with the silicon and sealed everything and everywhere.
I wasn’t going to take any chances. I really went overboard with the silicon (OB1 Multi-purpose sealant and adhesive from Screwfix)
For now I have saved myself around £420 by doing this myself. All I have to do now is to wait until it rains and see if any more water gets into my car. Until then, wish me luck!
Just about to do this to mine (with the same issue)! Thanks for writing about your experience. has it held the water out since?thanks matt
Hi Matt. It has held the water out from doing this since I did it. However I developed a new issue which fed water into the same area. The gasket under the fixings for the struts for the boot perished which in turn leaked into the same area. If you have a helping hand I would advise doing this as well. Undoing the bolts for the struts removing the gaskets and cleaning the area then using the same method of sealing as for the vents. In my case this was a silicon sealant. I would imagine that the boot around the wiring for the back screen will at some point perish as well, but I will be dealing with this prior to that happening and causing damage. If you want some more info give me a shout :)
Also be careful with the reversing sensors. The wiring was quite brittle so now I have 1 less working sensor lol