My Monte Carlo motor races in the morning when I start it up. Once I get to a stop sign I can shut the engine off, restart it and it doesn't do it, other times it will continue to race, and sometimes it will be normal when first starting it or shutting it off and restarting the first time of the day. Last night I drove 7 miles between 2 towns without never touching the gas pedal. It was if I had the cruise control on. Suggestions?