Water leak

[Bobgauntlett]

I have a 2003 rx. Which has developed a leak in the corner of the rear near side footwell.l know the sunroof pipes can get blocked but my roof is sealed to prevent it leaking

any ideas where this leak is coming from please 

[rich1068]

Hi Bob and welcome.

Have a search through the RX section and you'll find leaks are discussed. Don't limit yourself to the 300, the 400h sometimes suffers too.

I'd double check the sealed sunroof but also check the roof rail feet where they're fixed to the roof (easy to remove and reseal), seam welds around the tailgate and obvious stuff such as glass seals. Too far forward to be rear light seals.

[Stupot]

When you have an hour to spare, read this thread... it's possible that the membrane behind your rear door card has been messed with or a door seal gone etc... but water will settle at lowest point, so wherever you are experiencing water, the rear boot of the RX is probably the source because it can run from the boot into the cabin...see my write up below.

So....I was aware of the RX leak problems before I purchased my RX300 last month which indeed came with wet rear footwell carpets. The history showed Lexus had already had a go at fixing water ingress in 2014 swapping out the rear light gaskets.

I tested sunroof drains, they were OK and clear, sealed up boot lid hinge plate bolts...

I stripped out the rear boot floor/plastic trays etc. I sat in the boot of the car when it rained and watched water seeping in along the seams at back under boot lip exactly as per pictures on the last page of the above thread posted in March 2018 by 'Steve.ch'. No water came in from rear lights, so that was one possible ticked off the list.

Looking in the stripped out boot, I could see how water coming in could find it's way to the cabin carpets via gaps on each side of the 3 or 4 inch high crossbeam/bulkhead running just behind the rear seats. I had an idea!!!! I wanted to have a go at fixing the leaks in time, but I wanted dry carpets much quicker than that. So, a 'managed coastal erosion' kind of thing sprung to mind. I filled the gaps each end of the crossbeam/bulkhead with expanding foam, once dry, I sealed over with bathroom silicone sealant which I also ran along the seams the of crossbeam and in it's holes. My aim was to prevent water reaching the cabin from the boot. Secondly, there are several small rubber grommets covering 5mm-ish holes in several places in the boot floor. I removed these, now water can come and go as it likes without wetting the carpets.

I put everything back together and dried out the rear carpets as much as possible with swapping over towels with weights on them to sponge up the water... I also had an 8 hour drive to do over Xmas, so did this with heating on full aimed at the floor, sunroof open to vent the moisture (luckily no rain)

It's worked... the rear carpets are dry even after heavy rain. I can lift out the plastic trays and see only a cup full of water accumulates at the back of the boot after rain (our drive has a slope and I park rear down... old habit from the LS) before it runs out of the holes.... and now after the long drive, with no rain, the boot is bone dry because it's also getting ventilation via the opened grommet holes.

I might get round to fixing the actual source of the leak, but no rush now!

[Cotswold Pete]

Given both my LS suffered leaky boot syndrome (easily fixed), and the situation desrcibed here, it amazes me given that Japan has twice the rainfall of the UK, how the heck can Lexus owners manage in Japan when their cars get a little older.

My dads 20 year old Peugeot 406 (and when my wife had a 15 year old Honda) never had a leak in their lives!!!!

[Stupot]

19 hours ago, Cotswold Pete said:

Given both my LS suffered leaky boot syndrome (easily fixed), and the situation desrcibed here, it amazes me given that Japan has twice the rainfall of the UK, how the heck can Lexus owners manage in Japan when their cars get a little older.

My dads 20 year old Peugeot 406 (and when my wife had a 15 year old Honda) never had a leak in their lives!!!!

Well, the LS felt positively watertight to a depth of 30m in comparison to the RX sieve. 

[Stupot]

On 1/4/2020 at 12:39 PM, Stupot said:

how the heck can Lexus owners manage in Japan when their cars get a little older.

I have a friend who lived and worked in Japan for many years and he once told me a lot of Japanese like their cars to be nearly new... so they probably never get to the leaking experience and why there is such a healthy export market from over there.

[plastic orange]

All RX 300's must be the same as regards water leaks - had a deja vu moment when reading Stupot's experience lol. Since removing bungs, creating a dam between boot and pasasenger area and drilling some strategic drain holes, all is well. Took a while to get carpets dry though.. Shocking for what is meant to be a quality car though, and i don't think I'd have another.

 

Pete

[PCM]

On 1/3/2020 at 11:56 AM, Bobgauntlett said:

I have a 2003 rx. Which has developed a leak in the corner of the rear near side footwell.l know the sunroof pipes can get blocked but my roof is sealed to prevent it leaking

any ideas where this leak is coming from please 

Any progress on your leak?

[Claire W]

I have had a slow  steady leak for a few years with rear nearside carpets wet, now spreading across and down to the front nearside. Many garages have looked and just try the window seals and sunroof drain.  Looks like mine too is the boot, after reading your helpful threads, water is pooled in the boot after taking out trays. 
please could you tell me exactly where the bungs are to remove, and if i can do this from inside the car?

Just ordered tiger seal, hopefully that makes a difference, but carpets are ruined and smell awful. Its a  2005 model and I am hoping to run it as long as possible!!!!

[Spen]

Oh my lord - the water could be from the BACK!!

so my RX 300 is 18 years old. Had the leak in driver footwell for years. About ten years ago Lexus cleaned out the roof lines at great expense but problem was back the next year (I wonder if they realise this problem?!). But 2 years ago the electrics started to go wonky after a period of rain in autumn. It got progressively worse-and wetter.

I sealed the sun roof and looked for leaf blockage. No improvement. Took it to local garage-they tries but gave up after a while. So 18 months ago I bit bullet and went back to Lexus who wanted £450 just to look at it. After 3 days they decided the electrics were heavily corroded and almost at point of “blue death” (!). But they tidied it up and charged nothing extra -so not too bad to get a working car back! But no talk of the cause.

On return I sealed roof up again and bought a car cover. 18 months on its rainy season again and same problem. Now I have been using this cover but may have missed out on a few rain showers (got used to not using it in drier months). It’s even possible I’ve been lazy and only covered the food and left back uncovered a few times. But I’ve extracted loads of water with a carpet cleaner-twice, with rain cover permanently on-and it still comes back!

I’ve always parked my car on an inclined driveway-nose down. The above posts may have given me a light bulb moment!!!

Im going to park backwards now and see whether it dries out-don’t care if boot gets wet! 

Will report back!

Spen

[plastic orange]

Well, I sold our RX because of water and rust issues. Drilling holes seemed to work for me and making a 'dam' between boot and interior. When I said it was soaked, it was similar to throwing a bath mat in a bath full of water, and took weeks to dry out even with carpets lifted and me using a heat gun. When a car leaks with me, I move it on as it always brings other issues.

I'll never buy another RX.

 

Pete

[rich1068]

5 hours ago, Spen said:

Oh my lord - the water could be from the BACK!!

 

Have a look here Spen.