I have a 2006 PTCruiser and today I was going to change the plugs. I could not get them out. The engine was cold and I was using a 3/8 inch drive ratchet with a 5/8 spark plug socket. I was putting quite a bit of pressure on it and could not get it to turn. Is there a trick to removing the plugs? I don’t want to strip the threads in the head. I thought about an impact wrench, but wasn’t sure.