Did I really just flood my car?

October 29, 2009 8:55 PM

How easy is it to flood a car? I think I might have. Does it sound likely and what do I do next?

I drove down the street a little while ago (in the middle) and as I got further it got deeper. Enough to where I could hear it outside my car, if that makes sense. It was enough to splash at my lights with little effort by the time I got to turn around.
It was getting deeper instead of just being that deep to start with.
Instead of going further I turned back around. The whole sad trip didn't even last two minutes not counting the sitting in the drive (slightly elevated).

When I got back I sat outside and the car seemed fine. No water inside, all lights and battery seemed fine.I'm tempted to rin out and check since its been almost an hour.
Should I be worried or does it sound like a 50/50 at most? Will checking now cause damage?

posted by grablife365 to travel & transportation (24 answers total)

Did the car die necessitating extraction or did you drive it out of the puddle and sit there with it running? Make and model?
posted by Mitheral at 9:08 PM on October 29, 2009

If the engine never stalled, and water never entered the interior, the chances of permanent damage are pretty slim. When you ask if checking it now will cause damage, what kind of checking do you mean?

(Incidentally, usually, people use the word 'flooding' in relation to cars to refer to giving the engine too much gasoline when you're trying to start it, so that it won't turn over. This is easy to do in cold weather, or when your battery/starter/whatnot is starting to go bad. If you tell a mechanic that you flooded it, that's what s/he will probably assume you're talking about.)
posted by box at 9:08 PM on October 29, 2009

If you had really flooded the car, you wouldn't have made it home. You can really only do fatal damage, as far as I'm aware, if you get water into the air intake. Normally this is mounted pretty far up on the front grille, so as long as you didn't see water over the hood, you're OK. Also, the intake air filter will absorb a little splashed water before it saturates and starts letting water through. (I also suspect, although I don't know for sure, that the air filter would restrict the airflow to the point where the engine would stall before it let any actually get through. But I wouldn't depend on that.)

I suspect your car is fine, if it drove home OK. I've taken vehicles (mostly Jeeps) without fording kits through fairly deep water with no ill effects. Just let everything dry out thoroughly, and if you want to check one thing, check the battery and relay box. Everything else will probably be okay, unless you have problems (rust, especially rust holes) that you're not mentioning.
posted by Kadin2048 at 9:10 PM on October 29, 2009

The term you're looking for is hydrolocked.

You're only in trouble if water got into the air intake, which is in different places on different cars. Getting water in the engine is seriously bad, but you'd know it if it had. If it starts up again, it's fine. If not, new engine.
posted by hwyengr at 9:12 PM on October 29, 2009

Thanks for the answers.
Its a 2001 Volvo S80.
I didn't know if starting it up or do anything this soon could cause more damage somehow.
It never died and the floors and all felt fine, not wet.
posted by grablife365 at 9:24 PM on October 29, 2009

If your car didn't die, then it's probably just perfectly a-ok.

I drive my Subaru through all manner of standing water... including a two-foot deep stream the first summer I had it.

Most manufacturers are good about putting the air intake as far up in the engine compartment as possible, for just this reason.

(Incidentally, usually, people use the word 'flooding' in relation to cars to refer to giving the engine too much gasoline when you're trying to start it, so that it won't turn over. This is easy to do in cold weather, or when your battery/starter/whatnot is starting to go bad. If you tell a mechanic that you flooded it, that's what s/he will probably assume you're talking about.)

OP, pay attention to that. I came in here to tell you how to clear the gasoline from your engine. I finished your whole question and thought to myself, "Well, he must have stalled it in the water, then flooded it when it wouldn't start back up. But he skipped that part?" It took me a good couple minutes of contemplation to realize that you meant something related to water damage.
posted by Netzapper at 9:31 PM on October 29, 2009

: How easy is it to flood a car? I think I might have. Does it sound likely and what do I do next?

That's not something you need to worry about in this case. "Flooding a car" is actually a pretty deceptive phrase, when it comes down to it; it actually means pushing down on the gas pedal far too much when you're starting the car, so that the gasoline, which is supposed to shoot at the spark plugs and ignite, actually hits those spark plugs, wetting them, so that they can't cause a spark any more. When that happens, and the spark plugs are covered in gasoline and won't spark, the engine will turn ("RRURR - RRURR - RRURR") but won't actually start unless you wait for a minute or two and let the gasoline on the plugs evaporate. It's actually quite difficult to flood most modern (less than fifteen years old) cars.

As far as doing damage to your car by driving it into a deep puddle: again, most modern cars could probably handle at least a minute or two submerged as much as you seem to have been. It seems sort of amazing, but think about it: when you go to the car wash, one of the options is usually to have a high-pressure wash of your undercarriage. If spraying the bottom of your car hard with a jet stream of water doesn't do damage, then submerging the underside of the car shouldn't, either.

The thing you might have to worry about with some cars is that the floorboards might be flimsy and start to rot when they get wet. But I know that Volvos, especially modern Volvos like yours, are quite well-built under there, so I'll bet you're fine; if you have any particular worries, you should take the car to a Grease Monkey or other oil-change place and tell them you drove through a huge puddle and you'd like them to check to make sure you didn't do any damage under there. It'll won't take them more than thirty seconds, so they'll probably do it for free.

The only case in which you should be worried is if the water started to creep up your hood; there are a lot of electronics under there which need to be protected from submersion in water. But my recollection with the S80 is that the heat shield (that's a plate of metal or plastic underneath that protects the engine and other parts from flying rocks, et cetera) is pretty much water-tight and wouldn't let much water seep through.

Like I said: for peace of mind, you may as well take it to an oil-change place and have them glance at it, but you're probably going to be just fine.
posted by koeselitz at 9:39 PM on October 29, 2009

(Incidentally, usually, people use the word 'flooding' in relation to cars to refer to giving the engine too much gasoline when you're trying to start it, so that it won't turn over. This is easy to do in cold weather, or when your battery/starter/whatnot is starting to go bad. If you tell a mechanic that you flooded it, that's what s/he will probably assume you're talking about.)

All true, but only in cars with carburators. That doesn't happen with fuel injection.
posted by Chocolate Pickle at 9:40 PM on October 29, 2009

hwyengr: The term you're looking for is hydrolocked.

In the interest of explaining the terminology:

The basic gist of any car is: gasoline plus air plus fire equals ignition. That's really all a car is – simple as that – a huge machine designed to put gasoline, air, and fire together in the right place so they explode. Like I said above, flooding an engine stops the car because it prevents the spark. When people use the terms vapor-lock or hydrolock, they're talking about a problem that stops the car because it blocks the air flow.

What hwyengr and Netzapper mean is: it is possible for water to have gotten into your air intake and blocked the flow of air, or even sucked up into the spark plug area, so that the car dies. (Vapor-locking is when it's not water but steam that gets mixed up too much in the air; obviously steam isn't very good for a tiny explosion.) When hwyengr says that could kill your engine, he's talking about the disastrous effect that water would have if it actually got that far. Thankfully, this is nearly impossible with Volvos, and most cars for that matter; there would be a lot more dead cars if it weren't. What's more, even if just enough water got in to block the flow of air to the engine, your car would have died right then or at least within the next thirty seconds; since it didn't, it's highly unlikely that some pocket of water is in there somewhere just waiting to lock up your engine.
posted by koeselitz at 9:51 PM on October 29, 2009

Chocolate Pickle: All true, but only in cars with carburators. That doesn't happen with fuel injection.

Ah! I'd meant to mention that, yes.

That's because fuel injectors regulate the amount of gas that gets squirted on the spark. Carbureted engines have a whole system where air sucks the gasoline onto the spark plugs; basically speaking, it's a much easier system to mess up.
posted by koeselitz at 9:54 PM on October 29, 2009

So it's actually impossible for you to flood a Volvo S80; it has fuel injectors, not a carburetor.
posted by koeselitz at 9:55 PM on October 29, 2009

Chocolate Pickle writes "All true, but only in cars with carburators. That doesn't happen with fuel injection."

Sure it can. Most easily by firing the cold start injector or injection sequence several times with out actually starting the car or by wet ignition components prevent an engine from starting. Because of that in every injected car I've driven holding the pedal to the floor before starting cuts out the fuel delivery system allowing the rich condition to clear. It's called Clear Flood Mode.

grablife365 writes "It never died and the floors and all felt fine, not wet."

Your fine. The three main concerns are water getting in the intake which didn't happen or you'd know as your car would have died right there, the radiator fan blades being sucked into the rad which again you'd know because of all the sweet smelling steam and water soaking electronics. The under hood stuff can handle the occasional soaking in most cases. The concern is with electronics that were placed inside the car because they can't handle extreme environmental factors. Your carpets aren't wet so you are good on that score as well.

However check all your marker/tail/driving/head light housings to ensure they haven't trapped any water. The drains get plugged pretty easy in a lot of cases and water will take out your bulbs.
posted by Mitheral at 10:03 PM on October 29, 2009

When people use the terms vapor-lock or hydrolock, they're talking about a problem that stops the car because it blocks the air flow.

Hydrolock is actually when you fill the cylinders with something that isn't compressible -- such as water. Air (even with a bit of gasoline added) is plenty compressible; water isn't. An engine that has sucked in enough water to fill the cylinders can have all kinds of awful things happen to it. It's sort of a very small-scale answer to the old saw about an unstoppable force meeting something unmovable -- it turns out that water is quite unmovable and your engine parts aren't quite so unstoppable.

So the risk of driving through deep water the risk comes first from sucking water into the engine, and in the long term from getting water into places (your transmission, say) that it isn't meant to be, leading to corrosion and increased wear. You obviously didn't cause the first (because your car is still running) and you probably didn't go deep enough to cause the second.
posted by Forktine at 10:09 PM on October 29, 2009 [1 favorite]

And vapour lock is when a gas bubble develops in your fuel system preventing your fuel pump from delivering fuel to your engine. Mostly a memory now with the adoption of high pressure, tank mounted electric fuel pumps and recirculating systems.
posted by Mitheral at 10:39 PM on October 29, 2009 [1 favorite]

I spent the past year in South Carolina where the seasons basically boil down to sunny and rainy. During the rainy season, most of the work we did in the shop was water damaged cars. I replaced several hydrolocked engines and stripped out several interiors to replace wiring and computers that had been submerged and water damaged. The under-hood electrical connectors are pretty durable and weatherproof. The interior ones are not. I've pulled up carpets to find wiring harnesses floating in pools of water that's green and opaque from the copper oxide.
Check the carpet that's hiding up under the dashboard. There are often holes cut into the firewall that allow wiring to pass from the engine compartment to the car's interior. There'll be a rubber grommet that mostly seals that hole, but it's mostly to prevent wind and sound infiltration. They're not necessarily water tight and some water could have snuck through.
The carpet in your car is a few layers. There's the textile top layer, and then a couple other substantial layers of foamy insulation. That foam does a great job of trapping and retaining water, so do a really thorough check. Press down with your weight on the carpet. If water is trapped underneath, you'll force it to the surface that way and can determine if water is infiltrated.

Hydrolocking is an instant and complete death for an engine. We're talking major internal components being bent and broken instantly within seconds of being submerged. One time, I pulled the oil pan off of a hydrolocked motor and big pieces of engine fell out. There would be no mistaking this condition if you had done damage like this.

If you didn't have to get a tow from the deepest point of that puddle and your check engine light is off, then your engine is likely totally fine.
If you're concerned about starting the car and making sure that it's ok, pop the hood and have a look around before you proceed. In this thread, a MeFite recently drove through a puddle and wiped out their accessory belts. So, make sure they're all on their pulleys squarely, pull out your air filter and make sure it's dry, and make sure there's no standing water anywhere, like under the cowl (base of windshield area), or anywhere else.
Then, start it up, drive it, and make sure the Check Engine Light doesn't come on. Then, you're fine!

In the event that something is damaged, it's not uncommon for insurance companies to cover this sort of thing.

Good Luck!
posted by Jon-o at 5:15 AM on October 30, 2009

You might want to get your wheel bearings checked if you were submerged past the hubs.
posted by electroboy at 6:00 AM on October 30, 2009

You might want to get your wheel bearings checked if you were submerged past the hubs.

Without completely disassembling them, there's nothing to check, and that is not normal service behaviour - you'd just replace the wheel bearing and that is not at all necessary. If there is water damage, then the wear will be accelerated over the next few thousand miles - it's not like water will intrinsically damage the wheel bearings, just reduce the effectiveness of the grease inside it. Even if there was some wheel bearing consequence from this, I imagine it will be extremely minor (less than 5% of overall life of the bearing).

However, this is extremely unlikely as all automotive wheel bearings are pretty effectively sealed. There isn't much reason for this to be any kind of concern.
posted by Brockles at 7:12 AM on October 30, 2009 [1 favorite]

Well, by "check" I mean "disassemble and repack". It's not a big job.
posted by electroboy at 12:46 PM on October 30, 2009

It's not a big job.
Sealed bearings are extremely common, if not the exclusive wheel bearing technology of late model cars. The sealed unit is pressed in at the factory and, when it's time to be replaced, is subsequently destroyed in the process of being pressed out. I can't honestly think of a single car made since 2000 that doesn't use sealed bearings.
This is the style that Volvo uses and to remove the old bearings and install new ones requires the disassembly of the entire suspension in order to remove the spindle/hub bearing carrier and then press the old bearing out. Think 3+ hours each wheel to disconnect the strut, tie rod, brake hardware, control arms, press the hub out, press the bearing out, press the new bearing in, press the old hub back in, reassemble the suspension, and then perform an alignment after it's all back together.
This is, in fact, a big job. And is not the recommended course of action.
posted by Jon-o at 1:16 PM on October 30, 2009

That explains a lot. I've never owned a car made after '95. It also squares with my brother's description of Volvos as the worst car in the world to work on, thanks Jon-o.
posted by electroboy at 1:34 PM on October 30, 2009

It's probably all right if it didn't stall. If it turns over then you probably don't have any water in the cylinders so that's a good sign. I would probably get an oil change just to hopefully flush out any water, and keep an eye on any electrical weirdness: lights or windows that don't work or failures to start.
posted by chairface at 3:02 PM on October 30, 2009

I would probably get an oil change just to hopefully flush out any water

It is extraordinarily unlikely you got any water in your oil from this immersion. If the oil isn't leaking out, water won't be leaking in...

The engine is fine, the car is fine. The OP can stop worrying. They drove back out of the water and the car didn't even stall, hesitate or shudder so it is extremely unlikely anything at all happened - all the seals on the car worked like they were supposed to.
posted by Brockles at 3:57 PM on October 30, 2009 [1 favorite]

The car is fine. It ran as expected the morning after (yesterday?) and I haven't had any issues.
Thanks for calming my fears.
posted by grablife365 at 7:53 PM on October 31, 2009 [1 favorite]

Top Gear tried to destroy a toyota truck by leaving it in a tidal plain. It was completely submerged, in salt water, for hours, and was restartable after a bit of work by a mechanic (see 5:37 in the video).
posted by nomisxid at 9:01 AM on November 2, 2009