Consumer Reports breaks down your questions about washing your car

SAN FRANCISCO (KGO) -- When you go to the car wash, are you overwhelmed by all the options? Do I really need a tire and wheel cleaner? What about a special undercarriage wash?

Before you go all-in, listen to what our Consumer Reports car care expert has to say about car washes, so you are not throwing money down the drain.

Let's start with the basics: How often should you wash your car?

"I'd say at least once a week, at least once every two weeks. I guess that would be the norm," said one driver.

"At least once a week," said another. "Typically, every seven weeks roundabout," a driver admits.

What do the experts at Consumer Reports say? "It's not about doing it on a schedule," said Jon Linkov, Consumer Reports Auto Editor. "Instead, if you notice your car has mud, road salt, or grime on it, that's the time to wash it."

A good car wash is important to protect the paint and finish from dirt and other debris that can sometimes leave permanent marks like bird droppings, tree sap, and bugs.

And what about the dizzying array of extras and add-ons? Are services like wheel shine and spray on wax worth the extra cost to help protect the car? "Definitely skip the extras. They may make your car look nice, but they'll wear off fast," said Linkov.

But there is one car wash extra you should buy once in awhile, but not every time. "The undercarriage wash. Get it done once a season to clean road salt off after a winter and mud and grime off after a wet spring," shared Linkov.

Consumer Reports says automatic car washes tend to be less expensive than hand washes. They are a good option if you don't a lot of built up grime. But of course, you won't get the attention to detail that a hand wash offers.

Whether you choose an automatic or hand wash, how do you know if you've chosen a car wash that will actually get the job done right? "Check out the cars leaving the location, do they look clean? Super cheap car washes may use dirty towels, old, harsh brushes and rush your car through the process," Linkov said.

And try to find a car wash that sprays down the car before the wash cycle begins. Consumer Reports says pre-soaking will get you on the road to clean, shiny car.

If you prefer to wash your car yourself, remember using the wrong kind of soap, such as dish detergent, can strip a car's finish. And using sponges for cleaning, as many people do, can leave swirl marks in the paint.

Take a look at all of 7 On Your Side's stories with Consumer Reports here.

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