Some vehicles may exhibit a condition where the windshield
wipers chatter and/or wipe unevenly. Several items may contribute to this
 condition. To completely repair this condition, ALL of the items listed should
 be tested and repaired as necessary.
- Perform the wiper arm pressure test. Refer to 
Wiper Arm Tip Pressure Check 
 
- Inspect the wiper blade element set. Refer to 
Wiper Blade Element Check 
 
- Clean the wiper blade elements. Refer to 
Blade Element Cleaning 
 
- Clean the windshield glass. Refer to 
Windshield Glass Cleaning