When I take my foot off the gas at speed oil smoke emits from my tailpipe. My step-dad, who is a mechanical engineer says this mean I could need to rebuild my engine, is this true? Where should I start to alleviate this problem? Where is the oil getting into the cylinders? If I must rebuild the engine, and the compression is low, where can I get larger pistons after the engine is bored out? Thank you for any of your help.