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  • CulverCityHandCarWash

What's that on my car and why should I wash it off??!

Updated: Jul 1, 2021

We've all seen a car like this in our parking lot or driving down the road. A dirty car is not just a passive occurrence - that dirt is out there right now destroying your investment! And LA's climate is the enemy of our cars exterior and interior - constant damaging and drying UV rays, pollution and dust, nightly marine layer, sprinklers & landscapers blowing dust around. It all makes for a hostile environment.

Bird poop, Bee poop, Acid rain........Oh My!

Lets take a closer look at what's eating your paint.


BIRD POOP - is just gross!

It certainly diminishes the aesthetic appeal of your vehicle and is also unhygienic. Bird droppings can cause considerable damage to your vehicle’s paint as they contain Uric Acid and sharp grains. Its pH level ranges between 3 to 4.5, which is acidic. Uric Acid is corrosive and can cause damage to the vehicle’s wax coating and paint, causing 2 types of etching if left on your car. The 2nd type being the worst.

- Type I Stain Etchings are usually only topical, that is shallow enough that they can be completely removed by using a safe removal method

- Type II Wrinkled Etchings are usually too deep to fix safely. The problem is the paint fractures, (splits apart into tiny lines,), or wrinkles as the paint swells and bunches together.

Both can burn paint and clear coatings which is why it leaves a stain when it’s left for too long. What’s more bird droppings are also incredibly sticky. This is what enables them to bond to the clear coat and why it’s so crucial to remove bird droppings correctly as soon as you see it on the vehicle. Also, Never, EVER try to wipe off dried bird poop with a napkin or tissue directly from the paint as it will cause scratches.

For most of us - we just want this nasty gross stuff off our car and coming in for a hand wash is the best choice to let some one else do the dirty work for you. Our #ExpressWash is only $12.99, is quick and will save your paint from going to the birds. If your car is frequently bombarded by birds and notice some staining - we would recommend our #ExteriorPolish which combines the magic of clay bar treatment and our most popular Tech Shield application for correction and protection. Mention this blog post for %10 off!

In between washes we recommend Meguiar's Quick Detail. It's what we use on our own cars.

Unfortunately - we sometimes hear our customers say "why didn't these yellow spots come off, you didn't do a good job washing." Understandable to be frustrated if dirt remains after a car wash, who wouldn't be?

A lot of people assume it is only pollen but that’s not the case, it is so much more. So, what exactly are those yellow-gold dots? Simply put, it’s BEE POOP.

They are often round and yellow or, if on a windshield, long and yellow. These droppings are incredibly sticky and difficult to remove, even a regular scrub can leave them perfectly intact. Also, plain water is no match for bee poop. The most frustrating part about these spots is that they also contain bee wax, which is resistant to most carwash cleaning compounds. Although they seem to come right off with your fingernail, some cars can contains hundreds of these little spots, and there is no easy way to remove all of them at once. Our best advice is to have your car washed as soon as you notice these spots on your paint. The longer they have a chance to settle on your paint, the harder they are to remove, especially if they have been exposed to bright sunlight. Consider our weekly RegencyPlus car wash to cut down on the accumulation of dirt and bee poop. If there are alot of droppings, our TechShield may be necessary to remove them all meticulously and protect your car from further damage while lessening the need for washes.

INSECTS/BUG GUTS are another common culprit of damaged car paint. Similar to bird droppings, insect body fluid can be highly acidic and dissolve your paint. Another gross eyesore that can remain on the car even after a wash because of the sticky adhesion the guts secrete. While insects most likely won’t harm the surface upon initial contact, they can cause damage over time if left on your car. If you notice insects on your car, or after a roadtrip, we recommend our RegencyPlus wash so we can soak that gunk off while we do the dirty work for you.


Another natural element that can surprisingly eat away at your car paint. Over time, sap can eat away at your paint’s clear coat and cause staining and discoloration. If it’s hot outside, this process can be accelerated. It’s almost impossible to wash off using standard car washing techniques, and cleaner waxes, spray cleaners, and even solvents may be unable to remove this dried-on sap. This sticky substance can be tricky to remove, but it’s better to act sooner rather than later.

Tree sap is the enemy of your car's paint {LA Times Article}

This damage is definitely something that requires attention from one of our friendly and professional detail technicians - our Exterior Polish treatment.


The term "Acid Rain" refers to both wet and dry deposition of acidic pollutants that may damage material surfaces. Including auto surfaces!

These pollutant are released when coal and other fossil fuels are burned, react with water vapor and oxidants in the atmosphere and are chemically transformed into sulfuric and nitric acid, which is similar to battery acid. The acidic compounds then may fall to earth as rain, snow, fog, or may join dry particles and fall as dry deposition. Rail or brake dust is a prime example of dry deposition. Automotive exterior components, especially the painted surfaces may be damaged by all forms of acid rain, including dry deposition, especially when mixed with dew or rain. Learn more about acid rain from this interactive website EPA

Acid Rain can be as damaging to a car finish as stones, bird droppings, and tree sap.

It collects in droplets on your vehicle's painted surface. As the water evaporates, the acidic moisture eats into the painted surface. The process escalates when the sun heats the droplets and the paint. It produces three levels of damage: mild, severe and irreparable. The depth to which the acid has etched the painted or clear-coated surface determines the severity of the damage. {NY Times Article} This type of issue requires an Exterior Polish.


Ahhh - hard water spots - another common complaint that customers have after their car has been washed. Why are they still there???! To the untrained eye, all water spots appear to be same. You’ll notice that you can scrub some of the hard water stains away, but others will remain no matter how hard you work. That’s because they’re lodged tight into the microscopic surface of the clear coat and must be dissolved again to remove.

Generally speaking, there are three major types of water spots, all of which are caused by different sources:

Everything from dried-up mineral deposit remnants within a garden hose or sprinkler system (quite common here in LA), and acid rain infusing itself into a clear coat, the root cause of a water spot can be a complicated affair. This is one of the primary reasons why the automotive detailing community tends to categorize water spots as fitting into the following three stages.

- Stage I hard water spots can also be caused by rain that has become compromised by contaminants like airborne sand, pollution, and pollen - which we have in abundance in LA.

- Stage II, or “bonded mineral” water deposit. While this kind of water stain is also caused by contaminants or excessively hard water, the difference is that a Stage II water spot has been given ample time to more permanently “bond” with the painted surface’s clear coat. Like if you left your parked car on the street in front of a lawn with sprinklers.

Removal of a Stage II water spot often requires the leveling of the paint’s protective clear coat via the use of a hand-held rotary polishing tool and various cutting/polishing compounds. Our Clay Bar Treatment can also be used to remove certain Stage II water stains..followed by a hand wax or Tech Shield.

- Stage III water spots, now you're dealing with what is called “etched-in” water stains.

This type of hard water spot tends to look like a faded portion of clear coat, and is most prone to occurring on older, single-stage paint jobs that do not use hard clear coatings.

On the bright side, like all water spots, Stage III H2O stains are limited in that they cannot surpass the clear coat. This means they can be eliminated with many of the same paint correction techniques utilized during a Stage II water spot removal operation.

The only way to remedy the chemical etching once it has damaged the surface is to polish or wet-cut the clear coat to flatten it out.

If the layer is too thin, you’re looking at an expensive sanding down of the panel and respraying of the clear coat at a professional paint shop.


It is a known fact that excessive sun exposure damages human skin. Similarly, ultraviolet (UV) radiation can damage the exterior and interior of your vehicle.

Over time, sunlight begins to break down the molecules found in automotive paints, clear coats, and other materials, which causes it to be less reflective or transmitting less brilliance of ‘color’ that our eyes see. This is known as the dulling effect that UV light is responsible for creating with automotive paints, plastic trims, headlights, even automotive glass, tires, and wheels. Referred to as Oxidation. Over time, the paint will become visibly dull, rough and may even flake off in patches in more extreme cases. With California's sunny climate, I'm sure you've seen the cars with this damage and wondered what caused that. Now you know! And knowledge is power. If a garage isn't an option, a car cover is an alternative to protect your investment and extend a car wash.

- Minor Oxidation requires our Tech Shield treatment

- More extensive damage requires an Exterior Polish to repair and protect.

What if I can't tell the difference? Just stop by and our experienced detail staff can inspect your car and recommend the right service for your vehicle.

We also offer headlight restoration for those dull headlamps - just ask!


Sunscreen can very damaging to paintwork, and the longer it is left to dwell on the paint, the harder it is to remove.

The main reason for sunscreen staining a car’s paintwork is two of the main ingredients used in most sunscreen formulas – polyethene glycol and titanium dioxide. These are designed to reflect light and protect us from UV, but when accidentally put on a car’s paint, it will leave that white residue and if it’s left too long, it can damage the paint. Usually, the longer that this residue is left on the car, the worse the damage that will be caused! Same goes for the interior - simple cleaner cannot remove. If you find these marks after a day at the beach - stop in and we can take care of these for you with our Regency Plus wash.

Visual explaination of damage from these effects your car

If you can't park indoors - why not invest in a car cover? Here's a very affordable one we'd recommend.

Next post - Is Waxing a Car really necessary?


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