Tuesday, April 16th, 2013 AT 5:39 AM
My 1999 Pontiac Montana suddenly developed a loud knocking, sounds metallic in engine. My wife drove it, reported the knocking. I drove it no knocking. Then I drove it again, heard the knocking, drove it a little and it suddenly disappeared. Parked, started it again later, same noise. Just got gas yesterday, changed oil after the knocking started, don't see any metal shavings. Ideas?