6 Simple Reasons Why You Get Water Spots When Washing Your Car

You can tell a well-maintained car at first glance. It is pretty simple, like how you can see a dog loves its owner.

A properly kept car has clean interiors and a glistening outer appearance even at close range. A shiny surface doesn’t have water spots- the main culprit in degrading vehicles’ appearances even when new.

And, they can occur when cars are washed. So, why do the stains form when washing the vehicle?

Water stains occur due to failure to dry the car properly. Spending time cleaning the vehicle is one thing, but drying it well makes a difference. Failure to dry the car after washing leads to the water dwelling on the surface long enough to evaporate and leave mineral deposits, which are the stains.

Failure to dry the car after washing is one of the reasons behind water spot formation.

Other reasons include lack of paint protection and using dirty water to clean vehicles.

These reasons are discussed below; read to the end to learn more!

Why Do I Get Water Spots When I Wash My Car?

You may be surprised that you haven’t battled the unsightly stains alone; many vehicle owners have dealt with the same. It is frustrating to spend time cleaning the automobile, only for you to spot ugly marks on it once it dries. But what happens to cause them?

These are the reasons:

  • You used hard water to wash the car
  • You didn’t dry the vehicle properly
  • You used dirty, contaminated water to clean
  • The car was washed under direct sunlight
  • There was the use of filthy mitts to clean the car
  • Your vehicle lacks paint protection

Let’s explore them in detail below:

Using Hard Water to Clean the Car

Hard water is a major contributor to a vehicle developing water spots when it is washed.

The water has minerals like calcium and magnesium that make cleaning more difficult.

The minerals react with car shampoo to make scum, which is the last thing you need if you intend to clean the vehicle to a fault.

It is because scum overpowers the shampoo and reduces its cleaning effectiveness.

Hence, you will have a hard time forming lather to clean the vehicle, and the results will also be less-satisfactory.

Your car won’t be clean afterwards, and when it dries, unsightly water spots will be on the surface to mock your cleaning efforts.

Besides forming scum, calcium and magnesium remain on the surface once the water has evaporated after washing a vehicle.

These are the chalky marks you will see on the vehicle-the water stains many car owners have complained about.

Improper Drying After Washing

Another reason your car has spots when you wash it is the failure to dry it well.

Improper drying after washing leads to the water dwelling on the surface longer. Hence, it evaporates, leaving mineral deposits, contaminants, and impurities on the vehicle surface.

These remnants are the water stains that make your car appear ugly and dirty after washing it.

Using Dirty Water to Wash the Car

It may seem obvious, but some people are oblivious that using dirty water to clean their vehicles causes water stain-formation.

The water has all manner of dirt, impurities, contaminants and debris.

Rainwater is associated with all kinds of dirt, which many overlook because they think it is the purest.

It isn’t true because rainwater collects impurities during the water cycle.

So, when you use the dirty water to wash the automobile, you don’t rid it of dirt- you spread more of it instead.

You will see water spots as soon as the surface dries up, so you shouldn’t use impure water for vehicle cleaning.

Washing It in Direct Sunlight

Washing your car in direct sunlight is another reason why it develops water stains on the surface.

The sun accelerates drying; hence water evaporates off the vehicle fast as you are washing it.

You won’t have time to wipe the water with a clean microfiber cloth, and the mineral deposits remain on the car after the water evaporates.

You see the spots after washing your machine in direct sunlight.

The Vehicle-Washing Mitts Were Contaminated

If your vehicle develops watermarks when you wash it, look no further than the mitts you used.

Dirty, contaminated mitts have accumulated a lot of dirt in them, especially if you don’t wash them after each use. 

So, when you use them to wash the vehicle, your efforts are counter-intuitive.

You spread more dirt on the car on top of the one you were trying to clean, and there will be water spots once the water has evaporated.

Lack of Paint Protection on the Car

Your vehicle has water spots when you clean it because it lacks paint protection on the exterior.

Protective coatings like ceramics, waxes, and sealants have hydrophobic properties, meaning they repel water off the vehicle surface. 

Hence, the water wouldn’t dwell on the surface long enough to evaporate and leave water stains when you wash it.

You are facilitating water streaks formation on your car after exposure to water if you don’t coat it with paint protectants.

Can You Get Water Spots at Night?

As you have seen above, washing your car in direct sunlight is one of the reasons for water-spot formation on the surface.

Therefore, you may be curious; can your vehicle get water spots at night?

Your car will have water spots at night, especially if you park it outside. There could be overnight rainfall, leaving mineral deposits and contaminants on the vehicle. It happens when the rain falls with strong winds, accelerating the water drying and leaving stains on the surface.

Besides, parking your vehicle outside may expose it to sprinklers that splash it with water overnight.

The water dwells on the surface long enough to form stains because you aren’t available to wipe it off before it dries off.

Key Takeaways

  • Improper drying, using dirty water and mitts to clean, washing in direct sunlight, using hard water when washing, and lack of protective coatings lead to water stain formation on your vehicle when you clean it.
  • Your car can get water spots at night if exposed to water from rainfall or sprinklers.







Jan-Lucas Ganssauge
Jan-Lucas Ganssauge