What to do if you find water in your car

If your car has mould in it, chances are there will be water in it. If the car has steamed up windows then possibly there is water under the carpet somewhere.

If you can hear water sloshing around whilst you’re driving, then it's almost certainly there's water in it. If you have intermittent electronic problems such as your warning lights or central locking, or airbag light, then you may have water getting in the car somewhere. You will need to find your car's leak and fix it before more serious problems occur.

Seat removed and carpets lifted, so we can extract the water and dry the foam underlay.

One way you can find out is to feel the carpets to see if they are damp. Checked all the lowest points in the car. The low points in the boot/trunk. If you find water in the boot/trunk, then mop it up with a couple of old bath towels. Occasionally, your battery may be in there, so just be aware of your electrics. We recently had a car where the battery had been submerged, and it completely burns out the wiring loom. Chances are, if it’s just in the boot you can dry it out and then find the problem, fix it, test it, then check it a couple of times after it’s rained. Is the problem persists, then I would suggest spending a couple of hours on Google and YouTube as well as the other media to see if anyone has experienced the same problem with your particular model of car.  We have catalogued leaks we have found and recorded videos of them, so our video database of car water leaks is a good place to start.

For those of you with wet carpets, then you need to do pretty much the same thing, but you need to be aware that the carpets will need to be dried properly after you fix the problem. To do that, in 99% of small cars the seat(s) may need to come out, and the carpet will need to be lifted then water sucked out with a Wet-Vac several times over the course of a couple of hours. If it’s just on one side of the car. You can often just lift the carpet and put a bungee strap on the opposite handles (usually the ones that are on the headlining) which will hold the carpet up whilst you suck the water out.

Then the car will need to be dried properly. So for this, I suggest a plug-in fan heater which will have to be firmly secured in a safe place (not sitting in a puddle!) in the car, blowing the heat potentially onto the wet area. If the windows are open just about an inch, usually this will take possibly 2 to 3 days if the underlying foam is thick. On some smaller cars that have the thin foam, this can take only a day, depending on the strength and power of your fan heater. For cars with the carpets wet on both sides, then potentially you could do this on the other side as well without having to remove the centre consul and the carpet entirely.

"Drying the car out completely is crucial. If you leave water under the carpet, it will cause problems later."

This is the boot of a car which has had a leak. It's a fairly new car but as the interior isn't given the same level of paint protection as the exterior, rust can quickly set in, as has happened here.

Water ingress can lead to corrosion, smell and further electronic problems if you haven’t got any already. You may as well leave it a day extra to make sure, if you’re not sure whether it’s quite dry.

If you keep the ignition turned off, sometimes the car won’t recognise the seat was ever removed and refitted, so you won't get the airbag warning light come on -- if you do you will need a mechanic to reset it. Just in case you don’t know, most seats have a plug underneath them that you have to unplug to remove the seat.

Occasionally, if the ignition has been left on for any length of time, you will then need to reset the airbag settings. You can take it to a garage for this, or they do sell these gadgets, widgets, whatever you wanna call them online but be careful, most of them don’t do what they say they’re going to do. We use one made by a company called Foxwell.

Don’t put a car cover over it unless it’s only for a 1/2 day storm. If you leave it over it and there is water in the car, this will exacerbate every problem you have and give you more problems if you haven’t got them already. Mould loves this if there is still there something organic to grow on and darkness and, of course, water. A car cover can keep the moisture in and condensation will just get everywhere, so you need to put it in a garage temporarily or under a carport. Focus on keeping the car dry, or as dry as you can, using big bath towels.

If you have just water dripping from a high area, and it hasn’t soaked the carpets, then even a bucket in the right position with towels underneath it will do the job until you get it fixed. However, don’t assume that the one drip is all of the water source. We have had plenty of cars where it is dripping from the sun visor, but also running down the a-pillar and filling up the carpets.

Don’t take it to someone who doesn’t want to fix it. We see lots of attempts at fixing problems from people that are way into deep. We’ve just got a large hybrid Audi in at the moment, where someone has put bath sealant along the top of the back window on the outside. The car must be worth somewhere between £20,000 and £50,000 and this is an obvious bodge-job. Being a hybrid, it is of course full of electrics, and electrics don't play nice with water. Some of the terminals are powerful enough to kill you.

"Be aware that fully electric and hybrid cars can be dangerous with water in."

If your car has electrical problems, then it’s very difficult to advise you whether to drive the car or not, I suppose if I was ticking the boxes I would recommend don’t. It's better to be on the safe side. If your radio is not working, then you may decide to drive it, However if your ABS light has come on, then I would strongly advise against it. If you decide it's unsafe to drive, then don’t leave it parked for too long, because chances are, after a week or two, you will find mould, which adds another problem.

Found condensation in your car? Steamed up windows? You can see in this photo the rust on the brackets behind the dashboard. It can cause similar levels of corrosion to the electrical systems such as this fuse box.

For cars with mould in, that smell like there is stale water, or mildew, then I would suggest that you need to take it seriously because it can be a serious health risk. Mould spores get into you by getting into your air ways, and the risk of breathing it in and it infecting your lungs or sinuses is greatly increased in the enclosed space of a car. It can give you flu like symptoms, and potentially make you very ill. We have had quite a few people over the years that I’ve called that are too ill to drive their cars to us, and they haven’t worked out the connection between the mould and their illness. One lady even was off work for a couple of weeks, then went back to work in her mouldy car, and then was ill again for a couple of weeks and so on.

If you’re going to try to find a problem yourself, which sometimes does make sense, then be careful not to ruin the evidence that could help you find where the leaks are coming from. For example, if you think it might be leaking from the rear lights, then don’t pull the rear lights off and clean it and then put them back before checking if this was actually the source of the leak.

First, get somebody to get in the boot and test the backlight to make sure it is definitely that that is leaking before disturbing anything. Put a hosepipe on it, then have a torch on the other side. That way, you haven’t inadvertently fixed it and don’t know. Then it makes sense to do both lights as well as check the grommets and other pieces of plastic/seals around the area, as usually buy these are leaking as well. And of course, it’s worth doing them to avoid other problems later. After all, they are the same age as the seals or grommets.

Then after that, I would recommend you check it and then check it after it’s rained. You can sometimes fix one leak and then find there is more water there from potentially coming from another place. Typically, water finds it way to the lowest point in the car, so we have had cars where we fix the water leak and then there is more water at the same spot. As of course, we know that water finds its way to the lowest point. That’s usually one of all of the forefoot wells or in the boot, or sometimes in one or two of the door pockets.

Lastly, if you’re using a local garage, be kind to them, as potentially you’re giving them a quirky difficult job.

by Gary Wray
managing director

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