[big job]

Maybe I'm getting deaf; sounds like noise coming from the air cleaner. popping from
air cleaner means intake valve. you need a vacuum gauge. My bet, carbon on valve &
seats, gummed lazy valve guides, or possible weak valve spring. usually caused by lack of use. "the owner said it runs perfectly" and that's a when was that? well I use my car
every day 12 mo. a yr. bottom line; use it or you lose it.......