Cold Winter Means Drop in Fuel Mileage Returns

Dear Doctor: I own a 2002 Ford Taurus with 41,000 miles. This year I have noticed a large drop in gas mileage for city driving. It was rated at 20-mpg city, but now I’m closer to 10 mpg. My mechanic checked the spark plugs, wires, filters and everything looks good. What is he missing? Dan

Dear Dan: Loss in gas mileage during cold winter months happens for a couple of reasons. First, the difference in the winter blend gasoline will lessen gas mileage. The winter blend is designed to fire off faster in cold temperatures. Second, the engine will run longer in the closed loop mode because of the colder engine temperature. In the closed loop mode the engine operates in the preprogrammed computer mode. The engine runs richer and the transmission will sometimes not shift into overdrive or top gear. Oxygen sensors also get lazy with mileage, which are more noticeable in the cold temperatures. Engine oil also thickens and causes more drag on the engine. This is where as switch over to full-synthetic oil can make a big difference.

This entry was posted in Ford, Get Your Car Fixed -- Ask the Auto Doctor, More Car Quirks. Bookmark the permalink.