Car stalls in flood but now starts, does that mean the engine is okay?

Question

I drove my car (Fiat Panda Active) through a flood that was deeper than I expected, it stalled, I restarted it again, it struggled once more when I got out of the flood but kept going.

I then had the engine off for about 10 minutes to run an errand then drove for about 150 miles to reach my final destination, and my car drove fine all the way there.

I realise now that I shouldn’t have started the car in the flood (or attempted to drive through the flood in the first place without being absolutely sure of the depth!), and that I will need to check the oil for water contamination, but if my car started and drove okay does that mean I managed to escape ruining the engine?

Answer 1

Sounds like you've escaped a pretty costly deal, but if it's running and you're not seeing anything wrong, I'd say you're good to go. You need to check your oil to ensure there's no water in it. If there is, get it changed right away. Water in the oil will form acids which will eat your bearings and other soft parts. You can tell if there's water in your oil by if it is milky (looks like chocolate milk) as well as it being over full. Anyway, if you're driving it and there's no weird sounds or check engine light, you should be out of trouble.

Answer 2

You're not out of the woods - sorry.

First, water could have gotten in (via vents) into essential fluids - engine oil and transmission fluid. This will give you brown chocolate oil. The engine will run on that, and may eventually boil the water out of the oil (transmission fluid not so much)... but it will greatly increase wear on the parts, so it's taking years off the engine's life.

Second, "flood cars" are a scourge on the used car marketplace. What makes them so bad is that water gets into the electrical connections. If you look at electrical cable plugs and sockets on cars, they are very beefy with lots of rubber seals and gaskets. These are designed to keep out mist from the rain that gets by the radiator - they are not designed for immersion. When they are immersed, water does get inside them, and then, the fancy gaskets keep the water in. The water stays in there and corrodes the connectors incessantly. This does irreparable damage to wiring harnesses, and if you've worked with modern car electrical, boy howdy there are a lot of wiring harnesses! Cars are so electronic these days that water just wrecks them.

Obviously a 1943 Willys Jeep would be much more repairable. Even a 1969 Barracuda wouldn't be too bad.