Jeep Wagoneer/Commando/Cherokee 1984-1998

Evaporative Canister


See Figure 1

The function of the evaporative canister is to prevent gasoline vapors from the fuel tank from escaping into the atmosphere. Periodic maintenance is not required on any of the 1988-98 models (on all vehicles a sealed, maintenance-free, charcoal canister is used).

Some older model vehicles may have a removable air filter. The air filter in the bottom of the canister, if so equipped, should be replaced every 30,000 miles (48,000 km).

To determine if your vehicle has a canister filter, remove the canister from the vehicle and inspect the bottom of the canister for a filter.

In spite of the fact that this system requires no periodic maintenance, it is a good idea to quickly look over the hoses when servicing the PCV system. If any of these hoses is cracked, torn, or rotted, the result could be vacuum leaks and consequent poor engine operation, or an annoying smell of fuel vapor. If any of these hoses should require replacement, make sure to use a high quality replacement hose of a material approved for use in fuel bearing applications. Ordinary vacuum type rubber hose will not give satisfactory life or reliable performance.

The evaporative canister is mounted in the following locations:

All Grand Cherokee models-below the left front headlamp
All Left Hand Drive (LHD) 1984-97 models except Grand Cherokee-engine compartment on the right side frame rail
All Right Hand Drive (RHD) 1984-97 models-engine compartment on the left side near the heater blower motor
All 1998 Cherokee models-below the left side of the vehicle near the front of the rear axle

Click image to see an enlarged view

Fig. Fig. 1: The evaporative canister is usually secured in a clamp or bracket mount