What Causes Car Shaking After Driving Through Water Without Stalling?
2 Answers
High-voltage wires getting damp can lead to abnormal power supply to the spark plugs, causing engine misfire and resulting in shaking. Once the high-voltage wires dry out and power supply returns to normal, the engine will operate normally again. More extended information is as follows: 1. Inspection: Open the engine compartment cover, remove the air filter, and check for water ingress. If the air filter is dry, it indicates no water ingress, and the vehicle can be used with confidence. If the filter is wet, replace it and check the intake pipe for water ingress. If there is none, it means the engine hasn't taken in water, and the car is fine. 2. Slow Down or Stop to Observe: When encountering accumulated water while driving, if the water level exceeds two-thirds of the bumper or tire height, driving through it poses certain risks. Additionally, driving too fast through water can cause splashes to enter the cabin from the engine compartment or chassis. Always assess the water level; if it's high, try to detour and avoid forcing your way through.
Last time my car was shaking violently after going through water but didn't stall. The experienced mechanic immediately diagnosed it as water entering the ignition coils or spark plugs. Water seeping through engine gaps forms a conductive film, causing short circuits during high-voltage sparking and resulting in individual cylinder misfires. Another possibility is residual water in the air filter box, allowing water droplets to enter the combustion chamber with the intake air. The worst case is water accumulation in the exhaust manifold, where trapped exhaust gases cause abnormal cylinder pressure. Never force-drive with such vibrations - I've seen bent connecting rods in repair shops costing thousands to fix. Best to have the mechanic read trouble codes, focusing on ignition coil resistance and spark plug electrode condition.
