What is the function of a car's activated charcoal canister?
2 Answers
The function of a car's activated charcoal canister is: 1. To reduce the emission of gasoline vapors from the fuel tank and carburetor, directing the vapors into the combustion process and preventing their release into the atmosphere; 2. The canister contains activated material, and when the engine's solenoid valve is engaged during operation, the engine draws in the fuel vapors from the tank and the vapors adsorbed by the activated material into the intake manifold; 3. When the engine starts, the solenoid valve of the fuel evaporation purification device, installed between the activated charcoal canister and the intake manifold, opens, allowing the gasoline vapors in the activated charcoal canister to be drawn into the intake manifold for combustion. The principle of the car's activated charcoal canister is: when the engine is running and reaches medium to high speed, the solenoid valve is energized, opening the pipeline. The vacuum in the engine's intake manifold then draws the combustible gases from the charcoal canister into the cylinder for combustion. Simultaneously, external air enters the charcoal canister through the breather hole, flows through the internal absorption layer, mixes with the fuel to form combustible gases, and then flows into the engine's intake pipe. During this process, the activated charcoal in the canister is gradually restored due to the suction effect of the engine.
As an engineer friend who is quite passionate about automotive technology, the car's activated charcoal canister is primarily used to capture evaporated gasoline vapors from the fuel tank, preventing them from being directly released into the atmosphere and causing pollution. Simply put, this canister contains activated charcoal granules that adsorb these volatiles, and when the engine is running, the vapors are drawn into the engine via the vacuum system to be burned off. This not only reduces harmful emissions but also saves a bit of fuel. It plays a crucial role in the entire emission control (EVAP system), and now all new cars come standard with this component to meet environmental regulations. If the charcoal canister becomes clogged or damaged, such as when the activated charcoal ages and its absorption capacity declines, it can lead to unstable engine idling, difficulty starting, or the smell of gasoline. Therefore, it's important to regularly inspect the lines and replace components. Understanding this can help car owners reduce maintenance costs.
