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Look to be Fiero Stock EVAP "can" and will not work connected as shown.
Small port is Control vac that opens the Purge port and connected to Ported Vac port on TB/TBI on stock engines.
EVAP "can" for 3.8 just have a Purge line direct to the can without the valve.
Fiero and some others EVAP Canister are can shaped but that could be any shape to fit whatever space in another model.
To fix? use 2 vac lines to the can w/ small line to intake manifold so stay open w/ engine running allowing ECM/PCM to control Purging as diagram shows.
the other "Can shape" thing look like some crap vacuum reserve to keep vacuum but likely does nothing w/o check valve(s) plumbing into the right places.
Doubt the "tree ports" on the intake where several line connect have a check valve.
Vacuum Reserve "can" are used by Vacuum Operated Cruise Control and other things like Vac "Motors" used by many Heat/AC doors in thousands of models for decades. In some cases they add Big "Cans" or even Electric Vac Pumps to run Vac Boosted Brakes w/ engines can't make vacuum like some "performance engines" or E-cars.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave