Ah yes, the age-old question. Road film deposits that become trapped under the wipers cause streaks that appear on your windshield. After your vehicle has been washed and the glass is clean, the next time you use the wipers, all of that residue underneath the blade rubber gets streaked across your clean windshield. Here’s a quick fix:  dip a paper towel in white vinegar or window cleaner and run it across the wiper blades. No more streaks! Also, it’s a good idea to replace wiper blades at the first sign of wear. Most manufacturers recommend installing new wiper blades ever three to six months.