The EVAP system is put in place to absorb fuel vapors and release them to the engine intake during the times that it is running. It usually involves a canister filled with charcoal and which has connecting lines to the fuel tank, both ported vacuum and intake manifold vacuum. Fuel vapors are stored in the canister when the vehicle is not in use, purged by purge control valve while running, and consumed through the combustion process. Some of these problems include poor idling, stalling or even loss of fuel due to faulty CPV, damaged canister, cracked pipes or tubes as well as wrong hose connections. In order to address this problem, check hoses or replace them if necessary including any broken canisters. To change the canister: disconnect all of these vacuum lines; take off bolts attaching it to its mounting location; then reverse all these steps.