2002 Honda Civic smoking

I own a 2002 honda civic. I have maintained all service tining belt replaced, and new transmission. I was driving 65 mph on the highway when I lost all power to the gas peddle. I thought it might be the the fuel pump had it towed to the mechanics shop. The car sat over the weekend and was looked at by mechanic and the car started right up. My mechanic pulled the air filter cover off and informed me that there was smoke coming from under the valve cover through the breather hose. He told me that I might have a cracked cylinder or other internal engine problems. Does this sound right? I have not had a overheating problem and dont know what to do next any help would be appreciated Thanks