can you repair the plastic part on the side of the radiator
No, you can't. Just replace it they aren't that much money.
I tryied to repair mine one time it built up to much pressure and it was like it exploded.
Listen to bandit31so.
Looking for a Used Cavalier in your area?
CarGurus has 992 nationwide Cavalier listings starting at $695.
Search Chevrolet Cavalier Questions
Chevrolet Cavalier Experts