Just picked car up from shop,received tuneup,plugs,wires,adj. valves,all new belts,dist. belt,all new fluids.when driving i noticed a oil smell and then i noticed it coming from the heater vents.Is it just oil from the valve adj. on the headers and going thru the heater system?Car runs Great and they did take down the underbody cover.Seems to run a little hotter then before but today was a little warmer then usual . thanks