Will the engine water ingress warning light come on?
2 Answers
Engine water ingress warning light will illuminate. If the engine warning light turns on after driving through water, it indicates that water has affected the engine. Pay attention to the following aspects: 1. The car can still be driven, but the air filter is flooded: After the engine inhales air, it brings some water into the intake tract, forming water vapor. The water vapor mixes with gasoline and burns completely, having minimal impact on the engine. 2. A small amount of water enters the engine: When it reaches the cylinders and mixes with the engine oil, the oil quality deteriorates. Oil containing water will increase wear on engine components, potentially leading to increased engine noise and vibration during future driving. 3. The engine starts again but shuts off after a few seconds: This is the most severe situation. Since water cannot be compressed, when water enters the cylinders while the engine is still running at high speed, the inability to compress water during the power stroke directly causes the valves and connecting rods to bend, pistons to seize, severe cylinder wear, and crankshaft bending. It is recommended to change the oil as soon as possible. Some vehicle models are designed with the intake tract located on the fender or hood, and the height of splashes while driving through water varies, making it incomparable. Change the oil and blow the intake pipe clean.
I remember once driving through floodwater during a heavy rainstorm, with water rising up to the door frame. The engine ingested water and stalled. I was staring at the dashboard, but no warning lights came on—except the check engine light flickered briefly before going out. The mechanic later explained that water intrusion itself doesn't directly trigger dedicated warning lights, because sensors primarily detect internal engine faults like MAF sensor shorts or cylinder block damage before illuminating the check engine light. Water entering cylinders causes compression issues called hydrolock, which can destroy an engine outright. That repair cost me thousands—piston rods needed replacement. Painful lesson learned: never exceed half-tire-height water depth, and never restart a stalled engine in water. Drive safely, slow down in rain, and avoid risks. Now I detour around any standing water—after all, no warning light doesn't mean no danger. Prevention is key.
