Car stalled in floodwater: what to do, and what not to

Every rainy season, the same thing happens across Metro Manila: a car stalls in a flooded street, the driver tries to start it again, and a repairable car becomes an engine replacement. Here’s how to avoid that.

Don’t restart it

Engines compress air, not water. If water gets into the air intake and then into a cylinder, the piston can’t compress it, and something gives: usually a connecting rod. Mechanics call it hydrolock. It can happen the moment you turn the key, even if the water has already gone down.

So if the car stalled in water, or water came above the bottom of the doors, leave it off.

Get yourself safe first

Moving floodwater is stronger than it looks, and it can hide open manholes and drainage channels. If the water is rising, leave the car and get to higher ground. A car can be replaced.

Once it’s safe to reach the car

• Disconnect the battery. Open the hood and take off the negative (black, −) terminal. It protects the wiring and electronics from shorting. In a hybrid or EV, don’t touch the high-voltage system; follow the owner’s manual, or leave the battery alone and tell dispatch.
• Take photos of the water line on the car, inside and out, for your insurance claim.
• Don’t let anyone push-start or tow-start it. Rolling it in gear turns the engine over just like the key does.

Tow it on a flatbed, to a shop

A flooded car should go on a flatbed with its wheels off the ground. Water may be in the transmission and the wheel bearings too. Take it straight to a shop, not home, so they can check the oil, the air filter and the intake before anyone tries to start it.

During a storm, many drivers need help at the same time, so a truck may take longer to reach you. Dispatch will tell you what to expect when you call.

Insurance: Acts of Nature

Standard comprehensive car insurance in the Philippines often excludes flood damage unless your policy includes Acts of Nature (AON) coverage. Check your policy, and call your insurer before any repair work starts. They may ask for the photos you took and for the car to go to an accredited shop.

Saltwater is worse

In coastal areas like Malabon and Navotas, tidal floods are brackish. Salt corrodes wiring and connectors fast, so a car that sat in saltwater should reach a shop within a day or two, not a week.