What happens to cars caught in a flood?

This is the money shot from last night’s storms, as far as I’m concerned. Ruined food from power outages is a nuisance. A downed tree can still be firewood. But a car in a flood? That’s an awfully expensive paperweight.

This picture was taken in Roseville last night, apparently after the water had already receded somewhat.

This earlier tweet indicates that things do not bode well for the future of those cars.

And this one suggests there’s car shopping in the future.

More than likely, the engines are shot. The determining factor is whether they were running when the water came over the hood. If they were, the engine probably sucked water into the cylinders and a connecting rod or two probably snapped when the not-yet-flooded cylinders still developed enough power to try to push the piston in a cylinder already full of water. Something had to give with the pressure. The debris as the engine died probably blew its innards apart.

Here’s a personable explanation of what likely happened.

If, on the other hand, the car stalled because a tail pipe was underwater, and the working engine didn’t suck water into itself, then the engine, and thus the car, is probably OK, but for the expense of blowing water out (don’t try to start it), replacing some electronic circuits, and cost of the deductible from the insurance company.

This is why they tell us not to drive through standing water.

Related: Drying out your flooded car (Popular Mechanics)

  • jon
  • Mike Worcester

    It is not uncommon for disreputable car salespeople to buy those “flood vehicles”, dry them out, then re-sell them like nothing ever happened.


    • Jeff

      If you do research those cars I believe they have to show “salvage” on their titles.

      • johnepeacock

        Even if they show “salvage” unsuspecting Craigslist folk will get the story that someone had a “minor run in on the left bumper and the insurance company stamped it with a salvage title” – nowhere near what actually happened or what troubles the future buyer will encounter after a few miles.

    • kevins

      True…I bought one for one of my kids…a car that was in the Grand Forks flood of 1997. I even asked the sales person if the vehicle had been flooded, and he said no. Oh well, priceless lesson in trust for me and my family.

  • Robert Moffitt

    If they had been listening to me, they would all have been in Teslas. http://www.theverge.com/2016/6/20/11975452/tesla-model-s-floats-boat-elon-musk

  • Kurt O

    I had a car that didn’t get submerged enough for the insurance company to total it. It was OK for a little while, but it gradually became possessed. The engine would rev to 4000 at stoplights, and would accelerate up to 50 mph when I took my foot off the brake. It would slow down when I pressed the gas pedal and stall out. No mechanic that looked at it could figure out what was going on.

    At the very end one of the cylinders only worked about half the time. I was going to school in Chicago and had to drive it up to Milwaukee to trade it in (my mom had the title). My girlfriend at the time came along for the ride from hell up I-94 with the 4th cylinder slamming in and out. When we finally got there she said that if I didn’t get a new car that day she was taking a train home.

    After all that she still married me!

  • BJ

    After my time in the collision repair business. It’s not the engine that’s the problem. Electronics. That’s the death of these and why Insurance companies will total it. Diagnostics on that stuff is crazy.

    • 212944

      This. And mold.