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Driving Through Flooded Streets

  1. Sep 11, 2011 #1
    I know, avoid when possible, but I didn't see it until it was too late. I drove my 2002 Ford Mustang through maybe a foot of water for something like 10 seconds. It felt like it was about to stall but never did. On the drive home there were brief but occasional moments where the car would seem to lose some power as I shifted through the gears and increased the rpms. It seems like a transmission thing to me but I don't see how water could get in it if it keeps oil from leaking out. I'm pretty sure water didn't get into the intake, I think the engine is fine, so what are the most common dangers/problems associated with driving through water like that? Does anyone know why my car would act like this? Thanks.
  2. jcsd
  3. Sep 11, 2011 #2
    There are a few possibilities here.

    You could have sucked up water, and the loss of power was the engine bogging down while flashing it to steam in the cylinders (Believe it or not, some mechanics will trickle water into an engine while it's running to steam clean the cylinders, it's best when done with the cat converter disconnected though so you don't clog the exhaust).

    Possibility #2, You could have sucked up some water, and the loss of power was from the cat converter being clogged with crud from the cylinders.

    Possibility #3, Water could have entered a wiring connector or sensor

    Check the air filter; if it is wet, you sucked up water. Did the check engine light come on?... If it is on, get the codes checked; they will help to guide you in the right direction. Another thing, is it an automatic transmission or manual?
  4. Sep 11, 2011 #3
    Wow I never heard of that steam cleaning technique before, but it might've saved my rods from getting wrecked since liquid water is incompressible. I will check the filter this morning, and the check engine light has not turned on. It is a manual transmission.
  5. Sep 11, 2011 #4


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    Don't know if your car has a distributor or not but water under the cap is a common ailment. It will dry out eventually but best to take off and dry out.
  6. Sep 11, 2011 #5
    That's true, but I don't think the Distributor cap was compromised, there was no knocking/pinging or misfires. I think all of the electrical is fine, I'm wondering about mechanical ailments.
  7. Sep 11, 2011 #6
    I can't think of any real mechanical ailments from only being in a foot of water. Unless the serpentine belt slipped off, but I doubt that would even happen. You would notice it though (no power steering, battery light would be on).... I think he has a COP (Coil On Plug) ignition system which means there's no distributor. Not to mention he would have to be in a lot more water to reach that high on the engine.... If the intake is original OEM and not an aftermarket Cold Air Intake, the snorkel reaches pretty far down into the passenger fender. That's why I kinda thought that you may have sipped some water in there... With a manual transmission, there's not much electronics attached to the trans, But you may have gotten the clutch wet. That would lubricate it enough to make it slip a lot easier.

    After driving it again do you still notice the issue?
  8. Sep 11, 2011 #7
    Yes Allenman the things you've mentioned are correct, K&M aftermarket intake is in a relatively high position. The clutch getting wet makes the most sense, as it felt like occasional slippage when I shifted through the gears, I was also thinking maybe some water got in the muffler and created strong back pressures, but still think it's the clutch. Does anyone know why the clutch can get wet so easily? I just don't see how water got in the clutch if it's in the transmission case (though I did have to shift while I was in the water), maybe through the slave or master cylinder? I'm guna let it sit for another day to finish drying and then take it for a spin. If this is the case, shouldn't the water settle in the case (more dense than oil) and be easy to remove from the drain plug? I'll be sure to post what theory is correct.
  9. Sep 12, 2011 #8
    The clutch is not sealed in the transmission. It is in the transmission bellhousing in between the engine and the trans. The only thing there to keep stuff out is loosely fitting dust plates. Water would get in and out pretty easy.... You don't have to drain anything out of the pan because I don't think any water got into the sealed part of the trans or engine.
  10. Sep 12, 2011 #9
    Sweet! Sounds like good news to me, I guess I'll just use my work truck while it dries. Thanks, I'll confirm this when I know for sure.
  11. Sep 12, 2011 #10
    Might have gotten the knock sensor and/or O2 sensor connectors wet and caused some engine glitches; they wouldn't necessarily cause the engine light to come on.

    There is a vent on the transmission so some water could get in there but not much unless you had stopped in the water. Don't wait too long to check the drain plug and drive the car, you don't want the flywheel and pressure plate to rust if you did get water in there. Have a good look at everything when you're under there.
  12. Sep 19, 2011 #11
    Thanks to everyone for your input, the car is behaving normally again. As it turns out, Allenman was right, the exposed clutch got wet and temporarily degraded the power transmission between the engine and the gears. After letting it sit a couple days it dried up in the Arizona weather and was back to normal in no time. What a sigh of relief!
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