GM Full Size Vans 1967-1986 Repair Guide

Evaporative Canister



See Figure 1

Click image to see an enlarged view

Fig. Fig. 1: Common evaporative canister used on most full size vans

The only regular maintenance that need be performed on the evaporative emission canister is to regularly change the filter and check the condition of the hoses. If any hoses need replacement, use only hoses which are marked EVAP. No other type should be used. Whenever the vapor vent hose is replaced, the restrictor adjacent to the canister should also be replaced.

The evaporative emission canister is located on the left side of the engine compartment, with a filter located in its bottom. Not all vans have one.

To service the canister filter:

  1. Note the installed positions of the hoses, tagging them as necessary, in case any have to be removed.
  3. Loosen the clamps and remove the canister.
  5. Pull the filter out and throw it away.
  7. Install a new canister filter.
  9. Install the canister and tighten the clamps.
  11. Check the hoses.