I was looking under the hood of my car and I noticed a sizable crack in what I am assuming is the firewall cover. It is located in the engine compartment on the passenger side behind the engine. The plastic is very brittle and cracked more when I touched it. Is this a firewall cover and is it a big deal there is a crack?

Here'* a picture.
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Looks like your EVAP, part of the climate control system

crack not a big deal might want to seal it up with shiny tape though