Michigan motorists are getting quite a jolt at the gas pumps this week. AAA Michigan says the average gas price jumped nearly 32 cents from a week ago.  Michigan’s current statewide average is just under $3.70 per gallon, up more than 16 cents from this same time last year. The Auto Club says that the lowest average price among the cities it surveys, was found in the Marquette area at just over three-dollars-59 cents per gallon.   The highest was in the Grand Rapids area at more than $3.73 a gallon.