When your engine is flooded with petrol, it means that there’s too much fuel and not enough air in the engine. This causes the spark plugs to become wet and as a result they won’t be able to ignite the fuel. AA Roadservice receives many callouts due to similar situations.

Flooding a fuel injected car is more difficult than flooding one with a carburetor but it is possible. There are a few different ways to flood a fuel injected engine. Damaged injectors or a cold engine that won’t start can result in a flooded engine.

You can tell if your engine’s flooded when you spot these signs:

1. Very fast cranking (the engine sounds different when you turn the key – usually a ‘whirring’ sound)
2. A strong smell of petrol, especially around the exhaust.
3. The car doesn’t start, or starts briefly and cuts out again.

Usually, with a flooded outboard, time is your friend. If the engine’s flooded, wait for five minutes, then try to clear-flood start it. Regardless of the cause of the flooding, the clear-flood start works, even if you must repeat the process several times.

When an outboard boat motor “floods,” it has too much fuel in the cylinder. Gas-powered boat motors require a precise mixture of fuel, air/oxygen, and heat. When there’s an imbalance of these elements, the motor may fuel with an excess amount of fuel.

Wet. A wet spark plug can be the result of the engine flooding. You can clean the spark plugs or you can just wait for them to dry out.

The only place water can get into a sparkplug housing is from inside the cylinder. If it is water on the firing end of the plug then you have a head gasket or cracked cylhead or cracked bore or if a sleeve engine a porous bore.

A wet spark plug likely means that it hasn’t been firing due to engine flooding or a bad ignition cable. Dirt or moisture on the outside of the spark plug that provides a conductive path to ground, or an internal crack in the spark plug’s ceramic insulator that shorts the plug to ground also can be the culprit.

If water were to get into an engine cylinder it can cause the connecting rod to bend or destroy the cylinder head. Water can’t be compressed. The engine has to be “blown down” which is opening a valve on top of the cylinder head and applying “starting air” and watching for copious amounts of vapor.

When the coil gets wet, or there is moisture near it, there is enough of a path for some (or all) of the spark energy to get out right through the insulation. This in turn can lead to spark plug and ignition coil failure. Water intrusion is an unlikely, and therefore, overlooked cause of ignition coil damage.

ya, the easiest way is to take the plugs out and crank the motor over a few times to shoot the water out. Then let it sit over night with the plugs still out, and then try to start it again in the morning, or later in the day, and that should work.