What Causes Severe Shaking When Starting in First Gear?

[AlexisFitz]

Reasons for severe shaking when starting in first gear: excessively low temperatures and prolonged vehicle inactivity. Excessively low temperatures: Primarily due to extremely low temperatures where the lubricating oil is in a semi-solidified state and cannot fully perform its lubrication function. Consequently, the resistance during startup is greater than under normal temperature conditions, leading to shaking phenomena. Prolonged vehicle inactivity: The engine oil flows back into the oil pan at the bottom of the engine. Therefore, when starting the engine after prolonged inactivity (such as overnight), the upper part of the engine is initially without oil and lacks lubrication. It takes approximately 30 seconds after startup for the oil pump to circulate and deliver oil to critical lubrication points like pistons, connecting rods, and crankshafts.