What symptoms will a car show if the engine oil viscosity is insufficient?
2 Answers
Generally, several symptoms may occur: The oil warning light on the dashboard will illuminate. The engine temperature tends to run higher, and valve tapping noises may be heard. Knocking sounds can be detected within the engine noise. Below are detailed explanations: 1. Oil warning light on: When the oil indicator lights up on the dashboard, immediate oil replenishment is required. 2. Consequences of driving without sufficient oil: Firstly, lubrication effectiveness will significantly deteriorate. Secondly, in severe cases, lack of lubrication may lead to engine seizure. The less oil remains, the more severe the consequences. When restarting the engine, dry or semi-dry friction may occur between cylinders and pistons, accelerating component wear. Moreover, starting resistance increases substantially, making ignition more difficult.
I remember when driving, the engine suddenly made an extremely loud noise, roaring like thunder. When stepping on the gas pedal, it felt sluggish and weak, with painfully slow acceleration. Fuel consumption also skyrocketed—previously, a full tank could last 600 kilometers, but now it’s empty at 450, and the fuel gauge drops so fast it hurts to watch. Checking the engine oil, I found it was too thin, with insufficient viscosity to properly lubricate the engine components—no wonder wear and tear worsened. Once, during a long drive, the engine overheated and nearly stalled. Later, I learned that insufficient oil viscosity causes the oil film to thin, failing to effectively isolate metal friction, leading to overheating, accelerated aging, and component damage. Choosing the right SAE viscosity grade is crucial—like using 5W-30 in winter and adjusting for summer temperatures—to avoid regretting high repair costs later.
