oil filler neck cap

2002 cavalier. I can't get the oil filler neck cap off. Tried a pipe wrench (carefully) and can't get it to even budge. I'm afraid of breaking pieces of it off and having them fall into the oil pan. Any suggestions. Thanks

Mike

What engine do you have? Most of the Cavalier oil filler plugs are on the valve cover. Is that where your's is? It shouldn't be hard to unscrew it at all.