Rockville Auto Repair

You may have never thought about it, but when you turn a corner, the wheels on one side of your vehicle turn at a different speed than the other side.  What is this magic? The answer is something called the differential.   A differential is a gear box placed between the drive wheels and needs lubrication to work.  Over time, that fluid can become contaminated, reducing its effectiveness. You likely won’t be able to detect any signs that it’s happening, though it may get a little noisier over time.  If you continue to drive with contaminated and degraded differential fluid, the gears may wear prematurely. That can also contribute to excess wear on the drive-wheel tires.    Two-wheel drive vehicles have one differential while all-wheel and 4-wheel drive vehicles will have two or three.   Your vehicle’s manufacturer has guidelines on how often you should have the differential fluid changed, and we recommend you follow those.   Chan ... read more

Heat is one thing that can damage a vehicle, especially if a problem isn’t taken care of soon.  Be on the lookout for signs that it’s getting too hot in some parts of your vehicle, starting with the most obvious one: the heat gauge/warning light on your instrument panel. When you see that heat gauge heading into the H zone or the warning light comes on, it’s often because your engine’s coolant is contaminated or running low.  It’s important to let a pro look at it soon before serious damage is done, The radiator is another trouble spot that can cause overheating.  It has a fan that needs to run properly, and it needs to be free of debris and dirt. Another radiator trouble spot is the core.  When it gets clogged and coolant isn’t circulating as it should, an overheated engine can be the result. Have your cooling system checked regularly, including its thermostat. Your water pump is another part of the cooling system that can wear o ... read more

When your vehicle’s battery is dead, it leaves you with that horrible, helpless feeling.  A dead battery means it won’t hold a charge, and there are several reasons it won’t. One is age.  Batteries have chemical and electrical systems in them that create power, and as time goes by, they won’t work well anymore.  They may have been degraded by exposure to extreme temperatures, both hot and cold. Batteries have a code on them that can tell you when they were manufactured. Another reason your battery won’t hold a charge is corrosion on the terminals, the metal posts where your battery cables are connected.  A chemical reaction between the battery’s acid and air creates a salty moisture that can corrode those terminals.   If your vehicle’s alternator is not working properly, it won’t charge your battery as it is designed to, and the battery may lose its charge more quickly than it should. Another possibility is there ... read more

Regardless of whatever current gas prices may be, if you could use less gas, wouldn’t you? Well, here are 10 things that are robbing you of better fuel economy that you can change for the better:    •    Not enough air in your tires.  Underinflated tires have a smaller rolling diameter and more resistance to rolling.  Keep them inflated properly, plus ask us about more fuel-efficient tires.    •    Faulty oxygen sensor.  A faulty or dirty oxygen sensor can cause your engine to burn too rich a mixture of air and fuel.  That can also trigger a Check Engine light.  Have us check yours.    •    Oil age and type.  Contaminated or improper viscosities of engine oil can create more resistance in your engine.  Have regular oil changes and consider newer high-mileage oils.    •    Bad wheel alignment.  When your wheels aren’t lined up straight ... read more

When you start your vehicle’s engine, there’s another motor that makes that whole process possible.  It’s called the starter, and it’s a small electric motor that gets your vehicle running.   As you can imagine, it’s quite a chore for a little electric motor to turn over the big engine that powers your vehicle.  And after hundreds of successful starting missions, after a while, it will start to give out. You’ll know the starter is starting to give up the ghost when it turns too slowly or sometimes doesn’t do anything when you turn on the ignition.  Maybe it makes funny noises like grinding when you try to start your vehicle or maybe there’s just a click. Those are all reasons to get your vehicle over to us so we can see what’s going on.  A technician will make sure the problem is the starter and not in the battery, a switch, or other electrical component or connections.  If all of those are ruled out, y ... read more

Maybe your vehicle feels like Breaking Bad.  In other words, when you brake, things are bad.  You may find it takes you a longer distance to stop, you feel a vibration, or it’s pulsating when you depress the brake pedal, or perhaps your vehicle pulls to one side. Those can be symptoms of failing brake drums.  While a lot more vehicles these days have disc brakes, many vehicles still have brake drums, almost always in the rear wheels. The drum is a cast iron shallow cylinder that surrounds the other parts, including curved brake shoes that press pads against the drum to slow you down or stop the vehicle. Any time you have things going wrong with your brakes, you should get them fixed soon.  Safely operating any vehicle depends on having the brakes be able to slow and stop you dependably.  It can make the difference between avoiding a collision and having one.  When you bring your vehicle in, a technician will inspect your braking system. Depending on ... read more

What's the dif? To an automotive technician, it's the differential, a part of your vehicle that helps direct power from the engine to the wheels.  The differential is a gearbox that enables the drive wheels to turn at different speeds (they do that when you turn).   Inside the differential is a fluid that makes sure those gears and other parts are lubricated since there are a lot of metal moving parts in there.  (Your vehicle may have more than one differential in it depending on the drivetrain.)  As you can imagine, it's important that the lubricant in those differentials do its job.  Otherwise, the gears may be damaged by heat and friction. The more you drive your vehicle, the more likely it is for that lubricating fluid to break down. So, it's important to have the differential fluid exchanged every so often.  Your vehicle's manufacturer recommends how often your model should have that done, but a common interval is every 30,000-60,000 miles/50,000 km ... read more

While many components of your vehicle are complex and composed of lots of mechanical and electrical parts, there's one that isn't complicated but still important.  It's your engine air filter. (And, we should point out, the engine air filter isn't to be confused with the cabin air filter.  The cabin air filter cleans air that goes into the passenger compartment while the engine air filter cleans air that goes into the engine itself.) Why does your engine need a filter? Think of all the stuff–dirt, dust, and debris in the air¬–that gets kicked up on the road.  If that were to go unfiltered into your engine, it could damage other components. There are many different materials used in an engine air filter, including paper, cloth (frequently cotton), and other synthetic fabrics.  The material is usually folded tightly to maximize the filtering capability over a relatively small surface.   Before computers were employed to determine the proper mix of ... read more

Steering a vehicle these days doesn't take much effort, but if you got behind the wheel back before power steering was invented, you'd need to practically have the strength of Hercules to turn the wheel.    The first power steering systems widely available changed everything.  Chrysler introduced its Hydraguide power system in 1951. The "hydra" was for a hydraulic pump. It pressurized fluid that multiplied the force applied to the steering wheel so it was easier to turn the wheels on the ground. That pump got power from a belt attached to the engine, but unfortunately it wasted a lot of energy in the process. Plus, the system of hoses and pumps required a fair amount of maintenance and repair. Some say this system provides the most "natural" steering experience of power systems. Recently, automakers have turned to electric power steering.  It gets its power from the car's electrical battery and charging system and uses an electric motor to turn the wheels.  Sin ... read more

There’s an important part in your vehicle that shields your timing belt, timing chain or cam belt from the debris and gunk that can be kicked up from the road.  It’s called the timing cover.  It’s important because the timing belt or chain is what coordinates parts of your engine called the camshafts and crankshaft.  When they’re in sync, all runs smoothly.  When they’re not, it can cause some serious engine problems. If your vehicle has a timing belt, without the protection of the timing cover, that belt can come loose from the timing gears or break.  If your vehicle has a timing chain, the cover keeps engine oil circulating around it which lubricates it.  When that starts to leak because of a bad gasket, the chain may not be getting adequate lubrication.   If your vehicle has a timing cover problem, you may notice engine oil leaking if a gasket is not sealing tightly.  You may hear a strange metallic sound coming f ... read more