How to Repair a Vehicle’s EVAP System

This system is specially designed to prevent the discharge of gasoline vapors into the atmosphere. EVAP systems are different but they all have one similar component which is the Charcoal Canister. The function of this component is to store gasoline vapors from the vehicle’s fuel tank and carburetor float bowl until the engine is ready to burn them through the process of combustion.

The location of this component is in one of the distant corners of the engine compartment. Usually it is a black container containing charcoal pellets that are meant for absorbing fuel vapors. However every charcoal canister is not located in the engine compartment. Some canisters are mounted on some vehicles closer to their gas tanks for providing maximum efficiency.

Vehicle’s EVAP

The charcoal canister is attached to the gas tank through a series of hoses on a vehicle. It is designed to catch fuel vapors from the gas tank and then store them until the started engine can suck the flames out. This is also helpful with emissions as the flames are burned along with the fuel. If the charcoal canister needs to be removed for any reason, it can be easily done at home with ordinary tools. In this article, a 2001 Chevrolet Silverado vehicle is being considered. However, the process is similar to other vehicles also. Follow the directions.


Step 1:

Raise the vehicle using a jack and place it on jack stands. Before crawl underneath, make sure that the vehicle is secure.

Step 2:

Crawl under the vehicle to the driver’s side and locate the charcoal canister by the gas tank. This is ahead of the gas tank and has many plastic fuel-line connections going into it. Use the flathead screwdriver to disconnect those lines.

Step 3:

The charcoal canister has to be unbolted from the frame, use a 3/8-inch ratchet and socket for doing this task. Remove it from the vehicle by sliding the canister out of the bracket.

Tips and Precautions

  • Never smoke or use any ignition source near the vehicle when removing the charcoal canister. The fumes from the tank can ignite and can possibly harm you and damage your vehicle. While removing the canister, be sure not to keep any ignition source around. If it is needed to be kept open for a longer time then use a plastic bag and some tape for temporarily creating a strong seal around the lines