Rockville Auto Repair

Race car drivers have demonstrated the advantages of disc brakes, so most modern vehicles use them.  Sometimes just the front wheels have disc brakes, but many vehicles now have them all the way around.  A major component of the disc brake is called a caliper.  It works by squeezing brake pads against the disc or rotor, kind of like a bicycle hand brake.  The brake pads themselves are what contact the rotor, causing friction to build and the wheel to slow down, but it's the calipers that apply the pressure to the pads. Caliper design has evolved over the years, and there are two common types.  One is called a floating caliper.  It has one or two pistons on one side of the disc. When you push down the brake pedal, the piston or pistons in your caliper put pressure on that one side.  A mechanism connected on the other side of the disc applies pressure as well, squeezing your disc so the vehicle stops.  Floating calipers are less expensive since the ... read more

You look at it every day, yet you don't really see it.  We're talking about your vehicle's windshield, and if you're not seeing it at all, that's probably a good sign.  The fact is that unless our windshields get fogged up, hazy or cracked, we don't pay all that much attention to them.  Considering how vital front visibility is in a vehicle, paying a little more attention to your windshield will pay off in the long run. Keep it clean!  In ancient times when gas stations had attendants who filled your tank for you, they used to clean the outside of your windshield while the fuel was being dispensed. In these days of self-serve gas, we don't have that luxury any more.  But it's a good idea to clean your windshield regularly, even when it's not filthy. If you let dirt build up on the outside, it acts like fine sandpaper when you turn on your wipers when the glass is dry. Really, try to avoid turning on your wipers unless your windshield is wet.  If you must u ... read more

So winter has arrived and you don't feel confident in how your 2-wheel drive vehicle does in the snow and ice.  You envy all those people with all-wheel-drive (AWD) and 4-wheel-drive (4WD) cars, trucks and SUVs.  You start thinking, "I need one of those.  I'll be able to go anywhere without any worries."  The truth is there might be another option for you that you might not have thought of.  Sure, you've seen the ads that tout the advantages of AWD and 4WD, and some of the videos make it look like they can handle everything Mother Nature can throw their way.  The truth, though, is that vehicles with drive wheels at all four corners can't stop any more quickly than those with 2-wheel-drive.  Yes, AWD and 4WD vehicle have advantages when it comes to acceleration, but when it comes to stopping and handling, they generally don't.  If you buy a new AWD or 4WD vehicle, you are going to spend thousands of dollars.  Maintenance and upkeep costs are ... read more

Here's a part of your vehicle you probably don't think about much: lug nuts.  They're what fasten your wheels onto your axles.  Pretty important, right? In order to take the wheels off your vehicle to service the brakes, rotate the tires, etc., the lug nuts have to be in good shape so a wrench will grip them tightly.  Because lug nuts are on your wheels, they are exposed to all the elements of the road (salt, water, grime) and really take a beating. Unfortunately, some manufacturers have made them out of two different metals.  Underneath is the working part of the lug nut, made of steel.  On top is the decorative (the "good looking") part, made out of chrome, stainless steel or aluminum.  After a while, the steel part begins to corrode and expands.  That changes the shape of the outer cap, sometimes rounding off the hexagonal edges and making it hard (if not impossible) to either loosen or tighten the lug nuts since the wrench won't fit any more.  ... read more

Sometimes the movie is better than the book, sometimes it's the other way around.  But when it comes to your vehicle, the best book of all is the owner's manual. The plot is simple: Owner wants long life and dependable performance from the vehicle, manual has the way to achieve that long life and dependable performance. And yet, it's amazing that some people will own a vehicle for years and never even crack this book.  They'll only read it when they absolutely have to, for things like finding out how to change the clock.  Ok, so you're probably not going to rush right over to your glove box and start reading the owner's manual cover to cover.  We know that.  But just think of what you can get out of it. Consider this.  Those who wrote or helped write this book include the engineers who designed it and the people who tested and refined it.  They know more about your vehicle than anyone, period.  They know how long a part is likely to last and what ... read more

We've all seen drivers who do things that—let's be frank—really irritate us.  They're inconsiderate, can put people in danger and make the road a much less friendly place.  They really "T" us off.  These are the bad drivers who fit their description to a "T."  The Tailgater.  You've seen this terrible driver who follows a few inches off the bumper of the vehicle ahead.  We all know what's going to happen if the driver ahead of the tailgater has to slam on the brakes.  And we've all been that driver followed by the tailgater, whose vehicle fills up your entire rearview mirror.  The tailgater is likely not in a great frame of mind and, thanks to his or her stupid driving practices, the "tailgatee" is getting pretty ticked off as well.  That's a formula for a big problem. Know anybody who respects or likes a tailgater? Didn't think so The Texter. All sorts of people think they are perfectly capable of texting while driving.  I ... read more

Who thinks about their fuel gauge?  You probably don't… until it doesn't work any more.  Then you have to guess how much fuel is in your tank, and that's no way to live life on the road.  Fuel gauges, like every other part in your vehicle, can fail.  And when yours stops working, you will probably want to head over to your service facility soon, because no one relishes running out of fuel. The fuel gauge system is much more than just the gauge you can see on your instrument panel. Most systems have a float inside the fuel tank that goes up and down depending on the fuel level.  It's called the fuel sending unit, and it sends an electrical signal to the gauge (on the dash) telling it to display how much fuel is left in the tank.  So, what could go wrong?  Well, a few things.  For one thing, corrosion from bad fuel can cause it to stick and it won't move up and down any more.  So you could fill up your tank and the gauge would still rea ... read more

When someone mentions driving like a maniac, they're not talking about you, surely? Besides the safety issues of aggressive driving, you should know that your vehicle will last a lot longer if you'll just mellow out a little.  Here are four traits good drivers follow if they want their vehicles to go the extra distance. Cool—The driver who can't wait to get to the next stoplight is just shortening the life of his or her vehicle.  Jackrabbit starts and uneven acceleration hurts your engine because the valves and cylinder heads are stressed more.  All of those moving parts will wear out faster as well as other components that are connected.  That means things like the air conditioner, power steering pump… just about anything that attaches by a belt or a pulley.  Oh, and you'll be generating more heat.  Heat is one of a vehicle's worst enemies. Warm—If you get in your cold vehicle which has been sitting overnight, start it up and rev the en ... read more

You know you have an accelerator pedal; step on it and your vehicle is supposed to go.  But did you know there is a part in your vehicle that keeps track of where the throttle is? It's called the Throttle Position Sensor, or TPS. The TPS is a sensor that helps your vehicle figure out the right mix of air and fuel is reaching your engine.  It does that by keeping track of the throttle and sending that information to your vehicle's computer.  Other factors play a role in how well your engine is performing, including air temperature, how fast the engine is turning over and air flow.  When the TPS isn't working right, you may find your vehicle won't accelerate or doesn't have the power you're expecting when you press on the accelerator.  In some cases, it may accelerate on its own.  Sometimes your vehicle won't go over a certain speed.  Your Check Engine light may go on. Any of these symptoms should be checked out soon.  If your TPS stops working rig ... read more

The other day, a driver was trying to open his vehicle's hood so he could add some windshield washer fluid.  But when he pulled the hood release inside the car, nothing happened.  Usually, opening any hood is a 2-step process.  You pull the hood release (which is usually a handle under the dashboard to the left of the steering column) and listen for the hood to pop up slightly. (It doesn't open all the way because it has a safety latch to prevent you from accidentally opening it up while you're driving.) Then, you get out and find the latch, usually through the grille near the hood.  There's a little handle on it which you push, slide or pull (there are a few different types) at which point the hood can be opened up all the way.  But in this driver's case, the hood would not release at all when he pulled the handle inside.  Not knowing what to do, he called his service advisor, who told him to bring it over.  The reason? A hood with a broken latch cou ... read more