Rockville Auto Repair

When you hear hissing sounds coming from your vehicle, you might start thinking the worst.   One type of hissing coming from around your air conditioner may be a normal sound, or it could be a sign of serious trouble. First - the normal sound.  When you turn off your vehicle, the refrigerant goes from its high-pressure side to the low-pressure side. Some of those noises are normal.  But when it hisses all the time, that's another story. One cause could be that the refrigerant is leaking.  Air conditioners are fairly complex systems that involve various pumps, hoses, valves and motors.  When your air conditioner is cooling, the refrigerant changes from a gas to a liquid and back.  That refrigerant is under pressure, and there are many places it can leak from.  A hissing sound can also be a failed valve in your air conditioner's compressor.  It is what controls the refrigerant's pressurization.  It's important to have this fixed fairly qu ... read more

Air conditioning used to be a real luxury in a vehicle, but now it's standard in most.  Your vehicle's air conditioning system is built to last a pretty long time, but like anything mechanical, sometimes it fails.  It helps to know a little about how the A/C works. There's a compressor that pressurizes the refrigerant (you probably recognize the term Freon).  That makes it hotter, so it then goes through a condenser that cools it off.  Then another component takes out impurities and humidity before the Freon goes to a device that makes it lose pressure before it goes to the evaporator.  That's where it gets colder and takes the humidity out of the air. Then your vehicle's ventilation system blows air over the evaporator, cooling the cabin air that gives you such relief on a hot day. Of all these parts, one that does a lot of work is the compressor.  It has to compress that refrigerant and circulate it through the system.  It turns on and off several t ... read more

One of the most important things you can do to keep your vehicle running safely is to make sure your tires are properly inflated.  If one or more is vastly over- or underinflated, that has the potential to cause major handling problems and may result in a dangerous accident. All vehicles in recent years are equipped with Tire Pressure Monitoring Systems, or TPMS.  One system uses small sensors in the tires that continually check the pressure in each tire.  That sensor sends a signal to computers in your vehicle which turns on an instrument panel light warning of low pressure when at least one is very low. Or it may update a numeric reading on your instrument panel which gives you an approximation of how many PSI (pounds per square inch) of air is in each tire.  Another system works with your antilock brake system to measure the size of your vehicle’s tires.  When one wheel is going faster than another, it will spin faster. A computer sees that and alerts ... read more

Most of us know a bad muffler when we hear it.  That loud, rumbling sound is unmistakable. Did you also know you can get a ticket for driving around with a loud exhaust system? If your exhaust system has a leak in it, it may be allowing poisonous gases inside your vehicle and could make you seriously ill (or even kill you!) if you breathe too much in. Unfortunately, your exhaust system faces a lot of destructive forces out on the road.  Rust is the worst, and not just in colder climates where they use salt and brine as de-icers.  Exhaust systems can rust from the inside out when moisture condenses inside the pipes.  Vibrations and jolts from rough roads (and the occasional run in with a rock or a curb) can wreak havoc with exhaust systems.  Even a bad oxygen sensor can send too much fuel into the catalytic converter, and the resulting heat can wind up destroying this very expensive component. Your exhaust system is made up of several parts, and all need to be i ... read more

Bet you didn't know: Some of the earliest rearview mirrors were marketed as "Cop Spotters" so drivers would know when police were following them. Who wants a ticket, anyway? According to eBay Motors, Elmer Berger first patented a rearview mirror that was mounted on the front fenders, on the spare tire secured to the side of the car of at the top of the driver's door frame.  About 80 percent of your vehicle is recyclable. So says The Balance. That means four-fifths of most vehicles can be recycled.  Much of that recycling is done by automotive aftermarket recyclers.  Between the U.S and Canada, they reclaim enough steel to produce 13 million new vehicles. The man who invented the first modern cruise control couldn't even drive a car because he was blind! His name, says Smithsonian.com, was Ralph Teetor.  Blinded at a young age by a knife accident, Teetor was inspired to create a speed control by a couple of things.  One, the U.S. imposed a mandatory 35 mph/55 kp ... read more