What Causes Engine Idle Vibration After Driving Through Water?

[DiJocelyn]

Air filter clogging, high-voltage wire short circuit, low idle speed, and abnormal water temperature can cause engine idle vibration after driving through water. Air filter clogging: The air filter is designed to protect the engine and reduce wear. It is generally replaced every 10,000 kilometers or so. If not replaced in time, insufficient air intake can lead to low idle speed, causing the engine to vibrate. High-voltage wire short circuit: A high-voltage wire short circuit refers to the core wire of the high-voltage wire being short-circuited, which can affect ignition and cause engine vibration. Low idle speed: The engine idle speed value is preset in the car's computer. When the RPM drops below a certain range, the car's computer will automatically adjust it. If the idle speed is too low and causes vibration, it indicates that it has exceeded the computer's control range. Abnormal water temperature: The engine operating temperature has a normal range. High water temperature can cause advanced ignition timing, changes in the air-fuel mixture, thinning of engine oil viscosity, and reduced lubrication performance. Common causes of vibration include insufficient coolant, a stuck thermostat, a non-functioning fan, or an inaccurate temperature control switch. Solutions for engine idle vibration after driving through water: Clogged air filters can be resolved by simply replacing the filter element. A high-voltage wire short circuit can be checked with a multimeter to measure resistance, and the wire with significantly higher resistance should be replaced. For low idle speed, some cars have an adjustment screw on the throttle body to regulate idle speed, while others do not. For the latter, inspect the idle speed valve, throttle body, air flow meter, vacuum sensor, and adjust the ignition timing (for cars with distributors) to increase idle speed. Abnormal water temperature can be resolved by troubleshooting the issue.

[SanDante]

I've encountered engine stuttering after water exposure quite a few times in my driving life. Usually water gets into the engine compartment, potentially wetting the spark plugs or ignition coils, leading to ignition failure or intermittent misfires that make the car shake at idle. If water enters and blocks the exhaust system, poor exhaust flow can also cause vibrations. A soaked air filter affecting air intake is another common culprit. Post-fording, moisture may seep into electrical wiring or sensors - like when a waterlogged oxygen sensor sends chaotic signals that disrupt engine control. Never take this lightly; immediately pull over, shut off the engine, and check for wet spark plugs or blown fuses. It's best to have it professionally towed for comprehensive inspection, as water damage might hide deeper issues like ECU short circuits. Always control speed when fording and avoid forcing through deep water to prevent such troubles. Maintain water-exposed vehicles diligently - clearing undercarriage积水 and inspecting seals are crucial for故障 prevention.

[OKarter]

The idle shaking after wading through water is so annoying! I think it's mainly related to water intrusion into key components. Spark plugs may fail to ignite properly after being soaked, causing the engine to tremble. When the exhaust system accumulates water, unstable exhaust pressure can also cause vibrations. On the intake side, a wet air filter can interfere with oxygen supply. Another angle is electronic system failure, as water may cause short circuits in sensors like the crankshaft position sensor, leading to signal errors. I've tried simple checks myself: first, see if the spark plug cover is damp, pull it out and dry it; then check the condition of the air filter and fuses. If the problem persists, it might be a deeper issue like a short circuit in the ECU module due to water ingress. Taking immediate action after wading is crucial to avoid continuous operation damaging the engine. By the way, the risk increases significantly when the wading depth exceeds half the wheel height, so it's best to slow down when crossing puddles to reduce water splashing.

[RonanFitz]

The main reason for car shaking after wading through water is usually water entering the area near the engine. Damp spark plugs or coils may cause abnormal ignition, leading to unstable engine idling. Water accumulation in the exhaust system obstructs exhaust flow, which is another source of shaking. Sensors like the oxygen sensor may short-circuit when exposed to water, sending incorrect data and disrupting the control system. If shaking occurs, stop driving immediately to prevent further damage. It's advisable to visit a repair shop for professional diagnosis of spark plugs, wiring, and the exhaust system. Regularly checking the car's condition before and after wading can prevent potential issues. Wading through water poses high risks, so it's best to avoid deep water areas whenever possible.