What Causes a Burning Smell in the Engine Compartment?

[MirandaLee]

The causes of a burning smell in the engine compartment are as follows: Incomplete Gasoline Combustion: When starting the car in winter, the low temperature makes it harder for gasoline to atomize, affecting combustion. Some unburned gasoline molecules are expelled through the exhaust pipe and then enter the cabin via the external air circulation system. Brake Pad Friction: If the handbrake is not fully released, the brake pads will continuously rub while driving, producing a metallic burning smell. Alternatively, if the brake pads contain larger metal particles, a brief burning odor may occur as these particles wear down. Clutch Plate Malfunction: Slipping clutch plates in the transmission can generate high temperatures, leading to a burning smell. For example, when accelerating uphill with the clutch partially engaged (not fully lifted), the clutch plate and flywheel rapidly rub against each other, producing a scorched odor. Prolonged partial engagement with high throttle can easily cause the clutch plate to burn out.