The function of the evaporative emissions control system is to draw fuel vapors from the gas tank and fuel system, store them in a charcoal canister and route them to the intake manifold during normal engine operation. The most common symptom of a fault in the evaporative emissions system is a strong fuel odor. If a fuel odor is detected, inspect the charcoal canister, located in the engine compartment on 1996 Pathfinders, or under the vehicle on all other vehicles. Check the charcoal canister for damage and the hose connections for cracks and deterioration. On 1997 and later Pathfinder models the charcoal canister is located behind the left rear wheel. On Frontier and Xterra models, remove the spare tire for access. Check the canister and all hoses for damage and deterioration. The evaporative emissions control system is explained in more detail later.