All ActivityMost RecentMost LikesSolutionsRe: Breakdown InformationRV particulars: 1997 Fleetwood Bounder 28T Driveline (Engine, Transmission): Chevy 454 Miles: 35,000 Year: 2004 Break Down Description / Symptoms: Going up the hill out of Yreka CA the engine started making this sound like air was popping out of the cylinder with each stroke. Then there was a pop and it sounded a lot louder. Effect: I pulled over to the side and called for assistance. Cause: One of the spark plugs had come loose and popped out. Outcome: It didn’t take the threads with it, so they put a new sparkplug in and I was back on the road.