Noticed the charcoal cannister top, plastic, has two cracks. Should it be replaced and is the cover an integral part of it functioning. Looks like this one from ebay I may buy. Cracked along right and left side. 77740-06030

 

I wouldnt sweat it too much unless you are having CEL or performance issues. If you post a pic of yours maybe it would be better to gauge. Also, if the canister is relatively inexpensive then 'why not'?