Why Things Happen

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Why Does My Car's Windshield Wipers Leave Streaks on the Glass?

Windshield wipers are an essential part of driving safety, but streaks left behind by wiper blades can be frustrating and obstructive. There are several reasons why your car’s windshield wipers might leave streaks, and understanding these causes can help you take steps to prevent them.

Causes of Streaky Windshield Wipers

1. Dirty or Clogged Wiper Blades

Dirt, debris, and worn-out rubber on the wiper blades can cause streaks on your windshield. When wiper blades come into contact with a dirty or clogged surface, they can leave behind marks and residue.

To clean your wiper blades:

2. Incorrect Wiper Blade Angle

If your wiper blades are not properly aligned with the curvature of your windshield, they can leave streaks behind. Check your owner’s manual for specific instructions on how to adjust the angle of your wiper blades.

To adjust the wiper blade angle:

3. Insufficient Water Spray

Older vehicles with manual windshield washer systems might experience streaks due to inadequate water spray pressure or flow rate. If your car has a manual system, ensure you’re using the recommended amount of windshield washer fluid and checking the pump regularly for blockages.

To improve water spray performance:

4. Incorrect Windshield Washer Fluid

Using low-quality or mismatched windshield washer fluid can cause streaks and residue on your windshield. Always use a type of windshield washer fluid recommended by the manufacturer for your specific vehicle.

To choose the right windshield washer fluid:

5. Failing Wiper Motor

In some cases, streaks can be caused by a faulty wiper motor or worn-out bearings within the wiper assembly. If you’ve tried cleaning and adjusting your wiper blades without success, it might be time to consider replacing them or consulting a professional mechanic for assistance.

To diagnose and replace the wiper motor:

Conclusion

Windshield wipers leaving streaks can be frustrating, but identifying the underlying cause is often the first step towards resolving the issue. By cleaning dirty wiper blades, adjusting their angle, improving water spray performance, using high-quality windshield washer fluid, and diagnosing any failing components, you can enjoy clear visibility on the road.

Regular maintenance and inspections will also help prevent streaks from appearing in the future. Remember to always consult your owner’s manual for specific guidance on maintaining your vehicle’s windshield wiper system.


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