What is the function of automobile carbon canister?

Carbon canister is a kind of canister filled with activated carbon, which is a device to collect gasoline vapor and reuse it. Gasoline is very volatile, and with the volatilization, the pressure in the fuel tank will increase. In order not to cause danger, earlier people made the tank cover into the form of a pressure relief valve. When the pressure in the mailbox exceeds a certain value, the pressure reducing valve opens and the gasoline vapor is directly discharged into the atmosphere. Nowadays, gasoline is as expensive as gold, which seems to be a naked waste and is not good for the environment. So the gasoline evaporation control system (EVAP) appeared, and this carbon canister is an important part of the system.

How does a carbon canister work? When the vehicle is turned off, the gasoline vapor in the fuel tank is introduced into the carbon canister through the conduit and stored in the carbon canister through the adsorption activated carbon. After the engine is restarted, the solenoid valve located between the carbon canister and the intake manifold is opened, and the vacuum in the intake manifold generates a force to suck gasoline vapor in the carbon canister into the intake manifold to participate in combustion, thus achieving the dual purposes of environmental protection and fuel saving. Where is the canister in the car?

The carbon canister is located between the gasoline tank and the engine pipeline. It is installed in different positions on each car, both on the frame and near the front hood of the engine. Generally, there are only three pipes on the fuel tank. Both the oil supply pipeline and the oil return pipeline are related to the engine, and carbon tanks can be found along the remaining pipelines. Because the fuel line of the fuel tank is usually under the car, if it is difficult to do so, another method can be considered: look along the pipeline connected behind the throttle, sometimes the solenoid valve assembly will be integrated with the carbon canister, and then a rectangular box will be found on the plastic shell, which is where the carbon canister is located.

What faults often result from problems with carbon tanks?

Come on, too full to start? Many friends will encounter the problem that the engine is difficult to start because the fuel tank is too full. This is probably a problem with the gasoline evaporation control system where the carbon canister is located. The electromagnetic valve of the carbon canister is always open, so that all the gasoline vapor in the fuel tank enters the intake manifold, so that the computer detects that the mixer is too rich to start. Frequently closing the solenoid valve will lead to problems such as gasoline vapor saturation in the carbon tank, excessive gasoline vapor directly dispersing into the atmosphere, and strong gasoline smell in the car.

Failure of carbon canister leads to spontaneous combustion? Because the quality of domestic fuel is not high and there are many impurities in fuel vapor, the activated carbon particle holes in carbon tanks are easy to be blocked after long-term use. Blocked fuel holes make gasoline vapor nowhere to be discharged, which leads to excessive exhaust gas pressure in the fuel tank, cracks in riveted joints or other oil circuit joints in the fuel tank, oil leakage and spontaneous combustion accidents when sparks occur. Therefore, under normal circumstances, the carbon tank is inspected once every two years to eliminate hidden dangers such as oil intake and blockage of the carbon tank. Users who fill inferior fuel for a long time should shorten the inspection cycle.

The carbon canister on the car is an inconspicuous part, which is rarely mentioned by most users in daily maintenance. But this easily overlooked component is responsible for the absorption and emission of gasoline vapor. Regular inspection not only reduces the probability of oil circuit failure, but also can prevent accidents caused by oil and gas leakage before they happen.