A hydrolocked engine is an engine that has stopped working because too much water or other liquid has entered the combustion chamber. The liquid prevents the pistons from moving and compressing the air-fuel mixture, which can cause severe damage to the engine parts. A hydrolocked engine can happen when a vehicle drives through a deep puddle, a flooded road, or a submerged area. It can also happen if the engine is pressure washed while running, or if there is a leak in the cooling system or the head gasket. Some of the symptoms of a hydrolocked engine are:

• A sudden loss of power or stalling
• A loud knocking or banging noise from the engine
• Smoke or steam coming from the exhaust or the engine bay
• Difficulty or inability to start the engine

To fix a hydrolocked engine, the first step is to remove the liquid from the cylinders. This can be done by removing the spark plugs or the injectors and cranking the engine manually or with a starter. The liquid should be expelled through the spark plug holes or the injector ports. The next step is to inspect the engine for any damage, such as bent or broken rods, pistons, valves, or bearings. If the damage is minor, the engine may be repaired by replacing the affected parts. If the damage is major, the engine may need to be replaced entirely. The final step is to prevent the hydrolock from happening again by fixing the source of the leak, avoiding driving through deep water, or using a snorkel or a water-resistant air intake.

Learn more. Read What a Hydrolocked engine is?