almost the samething happend to me a week before NATS last year. when we started the engine it would do nothing but surge at low idle and you couldnt shut the engine off for nothing. I just so happen to run into the problem, with the chin cowling off and the plane upside down I flipped the prop over, to see it it had any compression it had some but not alot. but as I turned it over I saw a mist of fuel come from the head. turns out the valve cover gasket had a fold in it. man was that lucky.lol

Chris Odom
Team Black Magic
Team Dragon fire