What Causes the Abnormal Noise When an Automatic Transmission Car Starts at Low Speed?

[HenryFitz]

Automatic transmission cars may produce abnormal noises during low-speed starts due to: engine malfunctions, transmission issues, or door wear. Below are detailed explanations for each of these causes: Engine Malfunction: Abnormal engine noises, such as metallic screeching or whistling sounds, typically indicate problems within the engine compartment. These noises are often caused by excessive wear of certain components or improper assembly and adjustment. When such noises occur, prompt repair is essential to prevent further damage. Transmission Issues: If a "sandy" sound is heard from the transmission while driving, which disappears when the clutch or accelerator is pressed, or if a whistling-like noise occurs during gear shifting, immediate transmission repair is recommended. Door Wear: Abnormal noises from certain parts of the car body when accelerating or braking are often due to door-related issues, primarily caused by insufficient lubrication. It's important to determine whether the noise originates from the door hinges or internal components like the window regulator, door lock mechanism, or handle mechanism. For door hinges or limiters, a specialized door hinge and track lubricant should be used. For internal components such as the window regulator, door lock mechanism, or handle mechanism, a specialized door accessory lubricant is appropriate.