(Undated)  --  A new study by the RepairPal Institute shows Washington is one of the states where it's most expensive to have your car repaired.  The institute's Car Repair Index ranks Washington eighth in the country, with the average repair cost at 12-hundred-20 dollars.  Oregon, meanwhile, is ranked 17th, with the average repair cost at eleven-hundred-92 dollars.  Alaska is ranked as the most expensive, followed by Michigan, Connecticut, Massachusetts, and Missouri.