the lambda sensor has is a three pin plug, triangular shape......



what you have there is the plug to the purge valve that controls the carbon canister, for emission purposes they were fitted to cat models.

the canister is fitted under the drivers wing.

the wiring is connected to the ecu, so the valve opens on command, the engine can burn off the gasses that have been caught in the canister while the engine was switched off.
the valve itself is connected to the inlet plenum via vaccum hosing.