Rain Water Leaking Into Footwells

[DJDON]

I wonder if this is a common fault. The carpet in my 02, RX300 Gets soaked every time it rains. Mainly the passenger foot well but a little in drivers foot well too. It is not coming in through the sunroof. Looks more like the passenger door although I can see no obvious signs. The vehicle is in otherwise excellent well cared for condition.

It is wet also under the plastic trim at bottom of the door shut..Any advice would be well appreciated as its a lovely car in all other respects.I have owned it nearly 4 years, The problem has started a few months ago but is quite severe.Many thanks for you help.

[The-Acre]

I wonder if this is a common fault. The carpet in my 02, RX300 Gets soaked every time it rains. Mainly the passenger foot well but a little in drivers foot well too. It is not coming in through the sunroof. Looks more like the passenger door although I can see no obvious signs. The vehicle is in otherwise excellent well cared for condition.

It is wet also under the plastic trim at bottom of the door shut..Any advice would be well appreciated as its a lovely car in all other respects.I have owned it nearly 4 years, The problem has started a few months ago but is quite severe.Many thanks for you help.

It can be so hard to find the cause of water entering as there are so many ways it can come in. Does it happen when driving or just standing?

I know the two can't be compared but my other car (Vauxhall Vectra) has a common fault where the scuttle tray gets blocked with leaves and other muck. Instead of the water draining to the gound it builds up and comes in to the cabin past the pollen filter. When it happened to mine I was sure it was door seals or something like that. The problem is that you can't see the scuttle tray without lifting the plastic up under the bonnet. Mine had 3 years worth of gundge in it. I guess it could be that kind of blockage. Are you absolutely certain it's not the sunroof?

[DJDON]

I wonder if this is a common fault. The carpet in my 02, RX300 Gets soaked every time it rains. Mainly the passenger foot well but a little in drivers foot well too. It is not coming in through the sunroof. Looks more like the passenger door although I can see no obvious signs. The vehicle is in otherwise excellent well cared for condition.

It is wet also under the plastic trim at bottom of the door shut..Any advice would be well appreciated as its a lovely car in all other respects.I have owned it nearly 4 years, The problem has started a few months ago but is quite severe.Many thanks for you help.

It can be so hard to find the cause of water entering as there are so many ways it can come in. Does it happen when driving or just standing?

I know the two can't be compared but my other car (Vauxhall Vectra) has a common fault where the scuttle tray gets blocked with leaves and other muck. Instead of the water draining to the gound it builds up and comes in to the cabin past the pollen filter. When it happened to mine I was sure it was door seals or something like that. The problem is that you can't see the scuttle tray without lifting the plastic up under the bonnet. Mine had 3 years worth of gundge in it. I guess it could be that kind of blockage. Are you absolutely certain it's not the sunroof?

Thank you for your reply. It is certainly not coming in from the roof. I have checked under the bonnet & does not seem to be blocked up.The odd leaf or two but nothing major. Yes it happens when the car is stationary

[The-Acre]

I wonder if this is a common fault. The carpet in my 02, RX300 Gets soaked every time it rains. Mainly the passenger foot well but a little in drivers foot well too. It is not coming in through the sunroof. Looks more like the passenger door although I can see no obvious signs. The vehicle is in otherwise excellent well cared for condition.

It is wet also under the plastic trim at bottom of the door shut..Any advice would be well appreciated as its a lovely car in all other respects.I have owned it nearly 4 years, The problem has started a few months ago but is quite severe.Many thanks for you help.

It can be so hard to find the cause of water entering as there are so many ways it can come in. Does it happen when driving or just standing?

I know the two can't be compared but my other car (Vauxhall Vectra) has a common fault where the scuttle tray gets blocked with leaves and other muck. Instead of the water draining to the gound it builds up and comes in to the cabin past the pollen filter. When it happened to mine I was sure it was door seals or something like that. The problem is that you can't see the scuttle tray without lifting the plastic up under the bonnet. Mine had 3 years worth of gundge in it. I guess it could be that kind of blockage. Are you absolutely certain it's not the sunroof?

Thank you for your reply. It is certainly not coming in from the roof. I have checked under the bonnet & does not seem to be blocked up.The odd leaf or two but nothing major. Yes it happens when the car is stationary

Just another thought. Has it suddenly started or has it been gradual? If it's been a sudden leak it could well point to a blockage. I say that because my LS was fine one day and soaked the next, and the blockage was only small, and when I say soaked I mean dripping from the roof like rain drops. It seems a fairly common complaint on the RX (looking at the American sites) having wet carpets, but none seem to point to rainwater, mostly the AC system.

I don't know what else to suggest, apart from some detective work with a hose pipe. Hopefully someone else will have some ideas. I guess you've checked the obvious like drainage holes in the doors? In fact I think I'm right in saying the drainage from the sunroof on the LS can sometimes disconnect near the boot causing leaks.

Many years ago I bought a Chevrolet, a big beast! Every time I drove it I could hear a slight knocking from the rear, it drove me nuts. After some detective work I found that a whole wing at the rear had filled up with water and there was a small piece of plastic floating on top tapping against the body evry time the car moved. There's some useless information for you!

[DJDON]

I wonder if this is a common fault. The carpet in my 02, RX300 Gets soaked every time it rains. Mainly the passenger foot well but a little in drivers foot well too. It is not coming in through the sunroof. Looks more like the passenger door although I can see no obvious signs. The vehicle is in otherwise excellent well cared for condition.

It is wet also under the plastic trim at bottom of the door shut..Any advice would be well appreciated as its a lovely car in all other respects.I have owned it nearly 4 years, The problem has started a few months ago but is quite severe.Many thanks for you help.

It can be so hard to find the cause of water entering as there are so many ways it can come in. Does it happen when driving or just standing?

I know the two can't be compared but my other car (Vauxhall Vectra) has a common fault where the scuttle tray gets blocked with leaves and other muck. Instead of the water draining to the gound it builds up and comes in to the cabin past the pollen filter. When it happened to mine I was sure it was door seals or something like that. The problem is that you can't see the scuttle tray without lifting the plastic up under the bonnet. Mine had 3 years worth of gundge in it. I guess it could be that kind of blockage. Are you absolutely certain it's not the sunroof?

Thank you for your reply. It is certainly not coming in from the roof. I have checked under the bonnet & does not seem to be blocked up.The odd leaf or two but nothing major. Yes it happens when the car is stationary

Just another thought. Has it suddenly started or has it been gradual? If it's been a sudden leak it could well point to a blockage. I say that because my LS was fine one day and soaked the next, and the blockage was only small, and when I say soaked I mean dripping from the roof like rain drops. It seems a fairly common complaint on the RX (looking at the American sites) having wet carpets, but none seem to point to rainwater, mostly the AC system.

I don't know what else to suggest, apart from some detective work with a hose pipe. Hopefully someone else will have some ideas. I guess you've checked the obvious like drainage holes in the doors? In fact I think I'm right in saying the drainage from the sunroof on the LS can sometimes disconnect near the boot causing leaks.

Many years ago I bought a Chevrolet, a big beast! Every time I drove it I could hear a slight knocking from the rear, it drove me nuts. After some detective work I found that a whole wing at the rear had filled up with water and there was a small piece of plastic floating on top tapping against the body evry time the car moved. There's some useless information for you!

Actually it has been gradual over the past 6 months or so.I will re check more thoroughly the drainage holes & of course I did overlook the drainage hole in the roof. I said it was not the roof as there are no wet patches or visible signs of water on the headlining. I will check the roof again.I did think of the hose's & the matrix (had a matrix go in an old Toyota. steamed up bad but don't recall wet carpets.) All the hose's do look in perfect order.& no signs of water loss from the radiator. I will recheck all these points tomorrow.

As for the "useless information" (as you put it) lol .Not at all.I found it most interesting. I had a Toyota super saloon Crown X reg in the 1980s. You could sometimes hear water sploshing about under the car.Turned out to be water inside both front doors.. I removed the 2 or 3 rubber grommets from under the bottom of the door & a couple of pints drained out from each door. I left the grommets out & had no more problem. Again there was no wet carpet. I had an early 70s XJ6 that filled the petrol tanks up with water in a car wash one day.lol

Thank you for your reply.

[The-Acre]

I don't suppose the XJ6 still worked with the petrol tanks full of water??? If so, don't let the government know!

[DJDON]

Well thanks guys.i have found the problem. Silly me! "Certainly not coming in through the sun roof" I said...Well that is exactly where it is coming in from. in the bright morning sunshine I went out & opened the roof up. I noticed he drain hole on the passenger side (the side the carpet is saturated) was wet, although the drivers side not as bad but damp. I poured a drop of water around the passenger side drain hole & it just sat there. Nothing coming out from under the car. I did the same on the drivers side & it slowly drained away & poured out on the ground under the car.

The passenger side drain hole is certainly blocked up. How I unblock it I dont know. A metal coat hanger is too small. I am off now to find a 7ft welders rod or something that I poke through the drain hole untill it come out the bottom of the car. I will of course do both sides. it will take 2 minutes to fix it but finding something long & thin to go through that hole could take a little longer.lol

Thanks again for your your help. I was convinced it was not the roof or hose's but more door or window seal's. but what you guys were saying made me recheck & I have found the problem. "Blocked up drain hole's on the sunroof"

Much appreciated.

By the way the old Jag unfortunately did not like watered down petrol.

[bluenose1940]

See if you have a length of cooker cable (6mm or 10mm)lying around or, if you know an electrician see if you can cadge some from him. You will need to strip the outer sheathing off but leave the inner on, i.e. the red or the black sheathing and just use one of these lengths. You could try ordinary mains cable I have often used this for such jobs as whilst being flexible it is also very strong. Ordinary mains cable is only 2.5mm but still might do the job. Hope you crack it.

Well thanks guys.i have found the problem. Silly me! "Certainly not coming in through the sun roof" I said...Well that is exactly where it is coming in from. in the bright morning sunshine I went out & opened the roof up. I noticed he drain hole on the passenger side (the side the carpet is saturated) was wet, although the drivers side not as bad but damp. I poured a drop of water around the passenger side drain hole & it just sat there. Nothing coming out from under the car. I did the same on the drivers side & it slowly drained away & poured out on the ground under the car.

The passenger side drain hole is certainly blocked up. How I unblock it I dont know. A metal coat hanger is too small. I am off now to find a 7ft welders rod or something that I poke through the drain hole untill it come out the bottom of the car. I will of course do both sides. it will take 2 minutes to fix it but finding something long & thin to go through that hole could take a little longer.lol

Thanks again for your your help. I was convinced it was not the roof or hose's but more door or window seal's. but what you guys were saying made me recheck & I have found the problem. "Blocked up drain hole's on the sunroof"

Much appreciated.

By the way the old Jag unfortunately did not like watered down petrol.

[The-Acre]

Well thanks guys.i have found the problem. Silly me! "Certainly not coming in through the sun roof" I said...Well that is exactly where it is coming in from. in the bright morning sunshine I went out & opened the roof up. I noticed he drain hole on the passenger side (the side the carpet is saturated) was wet, although the drivers side not as bad but damp. I poured a drop of water around the passenger side drain hole & it just sat there. Nothing coming out from under the car. I did the same on the drivers side & it slowly drained away & poured out on the ground under the car.

The passenger side drain hole is certainly blocked up. How I unblock it I dont know. A metal coat hanger is too small. I am off now to find a 7ft welders rod or something that I poke through the drain hole untill it come out the bottom of the car. I will of course do both sides. it will take 2 minutes to fix it but finding something long & thin to go through that hole could take a little longer.lol

Thanks again for your your help. I was convinced it was not the roof or hose's but more door or window seal's. but what you guys were saying made me recheck & I have found the problem. "Blocked up drain hole's on the sunroof"

Much appreciated.

By the way the old Jag unfortunately did not like watered down petrol.

Glad that's sorted!

Because mine got so wet everything electrical went nuts. Apart from the alarm going off, the central locking went funny, the courtesy lights in the footwells stayed on, I really thought it had caused some serious damage. Fortunately when it dried out everything went back to normal (apart from the fact I haven't been able to use it now for over a week as I'm still waiting for parts)

[DJDON]

I found a length of curtain wire. (The type the wife would hang her nets up with) Was a perfect fit & did the job lovely. it went through easy & the water is now draining under the car like it should. Cost £4.95 but since found another tool available from "Ashley" housewares. a 3m Metal sink & drain cleaner. (Product code :-DL101) Cost £1.99 it is 10ft long & would also be a perfect tool for the job.

Thanks again for not only your help but because you actually really cared. You are true Lexus lovers.

[diagwebb]

On 1/6/2012 at 6:33 AM, DJDON said:

Well thanks guys.i have found the problem. Silly me! "Certainly not coming in through the sun roof" I said...Well that is exactly where it is coming in from. in the bright morning sunshine I went out & opened the roof up. I noticed he drain hole on the passenger side (the side the carpet is saturated) was wet, although the drivers side not as bad but damp. I poured a drop of water around the passenger side drain hole & it just sat there. Nothing coming out from under the car. I did the same on the drivers side & it slowly drained away & poured out on the ground under the car.

The passenger side drain hole is certainly blocked up. How I unblock it I dont know. A metal coat hanger is too small. I am off now to find a 7ft welders rod or something that I poke through the drain hole untill it come out the bottom of the car. I will of course do both sides. it will take 2 minutes to fix it but finding something long & thin to go through that hole could take a little longer.lol

Thanks again for your your help. I was convinced it was not the roof or hose's but more door or window seal's. but what you guys were saying made me recheck & I have found the problem. "Blocked up drain hole's on the sunroof"

Much appreciated.

By the way the old Jag unfortunately did not like watered down petrol.

 

I realize this is an old post but it helped me find the problem with my daughters 2000 RX300. Floors were completely soaked after a few days of heavy rain. I drew the sunroof back and on the passengers side of the "sunroof well" there was a standing pool of water and not on the drivers side. I ran some weed-eater nylon down the drainage hole and the water drained away out beneath the car. I poured more water down to be sure and it drained away too. Very helpful.  Thank you. 

[Haylands]

Just a word of warning, don't be tempted to use an air line to try to clear blocked sunroof drains, it can blow the pipes off inside the headliner and means many hours to refit...

[The-Acre]

1 hour ago, diagwebb said:

I realize this is an old post but it helped me find the problem with my daughters 2000 RX300. Floors were completely soaked after a few days of heavy rain. I drew the sunroof back and on the passengers side of the "sunroof well" there was a standing pool of water and not on the drivers side. I ran some weed-eater nylon down the drainage hole and the water drained away out beneath the car. I poured more water down to be sure and it drained away too. Very helpful.  Thank you. 

That's good news, well done!

[Louna]

I'm having the same issue with my Lexus RX 350 (2010). It has been six month and the back two floors are soaked after a rainy day. Any suggestions are appreciated. 

Thanks 

Louna

[Barry14UK]

Hi Louna,

I assume you read through this thread and have checked drains in sunroof cavity as these are most likely source as was eventually found. Whilst doing this check all 4 drains and clean cavity. Pour water through each drain one at a time to check water is coming out of bottom of car.  If no water coming out unblock drains 

If you don't have sunroof water ingress could quite likely be via scuttle. .

[Stupot]

My reply in another thread re water ingress on the RX....

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!

[Barry14UK]

Interesting you mention possible cause as membrane. behind the door card.  In many years of car ownership I have never had this happen until on my previous car, a 5 series BMW.  This is well documented problem with this car. Usually after 10 years or so the gasket can come 'unstuck' and some have success reactivating the adhesive using a heat gun but others have flitted a new gasket.  I was unaware that this could be a likely problem on an RX