1. The alternator is failing.
   There's a blown fuse.
2. There's a faulty bulb.
   There's a faulty exhaust gas recirculation (EGR) valve.

Have you ever noticed the indicator in your dashboard blink faster than normal? It's trying to tell you that it's time to change a light bulb.

1. It's clogged vents.
   It's a failing AC accumulator.
2. It's because of a faulty oxygen sensor.
   It needs a windshield replacement.

The AC accumulator filters moisture from the AC system, so when it's falling down on the job there may be -- stinky -- mold and mildew buildup. When diagnosing a bad AC accumulator, you may also find coolant leaks underneath the car or that there's a rattling sound when the system is turned on.

1. A crack in the cylinder head
   A crack in the engine block
2. A damaged head gasket
   All of these may cause the problem.

When everything is running properly, you'll see a light or a thin white exhaust vapor emitting from your vehicle. But if your car's exhaust is a different color, it may be time for a checkup. White or light gray exhaust smoke in particular may mean that the engine is burning transmission fluid -- and it will smell like burning oil. Alternatively, a leaky head gasket or a crack in the cylinder head can cause coolant to burn in the engine's combustion chamber, causing thick white exhaust smoke that smells slightly sweet.

1. Corrosion around the posts
   Excessive heat
2. Faulty electrical components or wiring
   Squealing belts

Batteries typically last about three years. You can tell if yours is drained or dead by looking for corrosion around the posts, a bloated battery case caused by excessive heat, or faulty electrical components or wiring. Don't fret: You can jump start a vehicle if the battery dies. But if it continues to die it means there is a larger problem -- at that point, you'll need to figure out what's draining it so quickly, or you may need to replace the battery.

1. It could result in poor handling and control.
   It could cause vehicle damage.
2. It could cause wheel damage.
   It could cause any or all of these things.

In addition to being hard to control behind the wheel, driving on a flat tire can cause damage to the tire, and it may also cause damage to the wheel and even to your vehicle, depending on the conditions. Always choose to put on your spare tire and leave the tire patching to the professionals.

1. The front airbags have been manually switched off.
   A severe engine misfire has happened.
2. You need to schedule an appointment for regular maintenance.
   You're not wearing your seatbelt.

The CEL is part of your car's onboard diagnostics system, the computer that monitors your car's performance including everything from regulating its engine speed to emissions monitoring. When the CEL is blinking, it usually indicates that your car's engine is misfiring, allowing unburned fuel to go straight into the exhaust system -- and that's a catalytic converter-damaging condition. This is one fix for the mechanic.

1. Driveshaft leaks
   Engine "knocks"
2. Powertrain control module failure
   Worn gear synchronizers

While a knock sensor is going to help minimize the damage in the short-term, long-term damage -- from poor fuel economy to severe engine damage -- can happen if you make a habit out of using the regular rather than premium octane fuel. Putting higher-octane fuel in a car that only requires regular, however, is just a waste of money.

1. There's a delay when you shift gears.
   There's a loss of engine coolant.
2. Transmission slips or grinds when the car is shifting gears.
   Vehicle shakes at any speed.

Gears slipping or grinding during shifting as well as a delay can both spell transmission trouble -- as can a car that shakes at any speed you drive it. In addition, you may also hear clunking or whistling sounds in neutral or smell a burnt odor from under the vehicle's hood.

1. Carburetor icing
   Engine run-on
2. Flooded engine
   Vapor lock

"Running-on" or "dieseling" is when an engine keeps running for a short period after being turned off. The problem happens in spark-plug-ignited, gasoline-powered internal combustion engines (not diesel engines), when fuel ignites without a spark in the combustion chamber. While it's rarely a problem in fuel-injected engines, it can be a common problem if your car has a carburetor.

1. A brake fluid leak
   An engine oil leak
2. A transmission fluid leak
   A washer fluid leak

Automatic transmission fluid is oil, but you can tell it's not engine oil or gear oil because it's a different viscosity -- and it's tinted red. Finding this reddish-brown fluid under your car is a sign of a possible transmission fluid leak.

1. A failing power-steering pump
   A worn fan belt
2. A worn serpentine belt
   Worn brake pads or rotors

Squealing and squeaking brakes isn't just loud and maybe slightly embarrassing, it could also be putting you and your passengers at risk. It's common, though, because of wear and tear, and usually caused by the aging of some of the components of your car's braking system: worn pads, "glazed" pads and rotors, broken anti-rattle clips, lack of pad insulation or insulation shims, or an incorrect rotor surface cut.

1. A bad turbocharger
   The blower motor resistor is bad.
2. The engine is flooded with gasoline.
   A faulty muffler

Black exhaust smoke suggests that the engine is being flooded with gasoline, and that black smoke is a result of unburnt fuel being forced out of the exhaust. It could be caused by a clogged air filter, a clogged fuel return line, a malfunctioning fuel injection system or a blocked manifold, among a few other potential issues.

1. The alternator
   The chassis
2. The ignition
   The transmission

The alternator is what keeps your car's battery charged while it's running. It allows the car's battery to supply power to all the electrical components -- such as the headlights -- seemingly endlessly. In addition to dim headlights, there may be other electrical issues, such as with power windows and seats.

1. Fake-wood fascia
   Pistons
2. Shock absorbers
   Spark plugs

A car that is hard to start and idles rough may need new spark plugs. Symptoms may also include a misfiring or surging engine, high fuel consumption and a general lack of acceleration.

1. A bad radiator
   A bad radiator hose
2. A bad radiator clamp
   Any or all of these could cause leaks

Finding green or orange fluid (it depends on the type you use) underneath your car is a good indication you've got an engine coolant leak on your hands -- and narrowing it down can be tedious since it could occur anywhere in the cooling system. Common culprits of an external leak? Besides overfilling the tank, coolant leaks often are a result of bad radiator hoses or clamps, a faulty intake manifold gasket or a faulty radiator itself.

1. Poor fuel economy
   Uneven tread wear
2. Vibration in the steering wheel
   All of these are signs a car's tires are out of balance.

The most common symptoms of unbalanced or out-of-balance tires are uneven -- and quicker -- tread wear and poor fuel economy. But the one you'll probably notice first is the vibration, which can be in the steering wheel, the floorboard or even the seats -- it'll worsen the faster you drive.

1. Its age
   Its color
2. Its smell
   Its temperature

Diagnosing a burnt clutch can be difficult without being able to smell it. Other problems that could cause clutch slippage include a bad flywheel, a misaligned clutch bearing, a blocked cylinder port -- or trouble with the associated cables and pistons that connect the pedal to the clutch itself.

1. A stuck "on" brake caliper
   Out of balance tires
2. "Out of round" brake rotors
   All of these can cause a car to shake.

Although the most common reason for a car to shake is related to its tires, it's not the only thing that can cause vibration between 50 and 60 mph. Brake problems, including "out of round" or off balance brake rotors or a brake caliper that's stuck on.

1. Flushing the fuel system
   Lubricating the fuel-injector pump
2. Rebuilding the engine
   Running the engine rough

Topped off with diesel instead of gasoline? Your car can only run on the fuel it's intended to use. Gasoline engines, for instance, use spark plugs to ignite fuel rather than the air compression of diesel engines. Because gasoline engines cannot combust diesel fuel, your car won't run on diesel fuel. It usually takes more than just siphoning it out of the tank. It's time to get the fuel system flushed, including the tank, fuel lines, injectors, rail and fuel pump.

1. Black
   Blue
2. Light grey
   Purple

The usual suspects when it comes to blue exhaust smoke are worn valves or valve guide seals, damage or wear to piston rings, or worn or damaged cylinders -- and that can allow oil to leak into the engine's combustion chamber where it mixes with fuel. In addition, you may notice the car's engine doesn't have the same power as it used to.

1. Radiator hose leaks
   A leaky CV joint
2. The ignition system is misfiring
   A bad rear differential

A quick drop in the coolant reservoir level is a good indication that your car has a radiator leak. Check your radiator and its hoses for leaks, swelling, or holes, or if there are any collapsed, cracked or soft hoses.

1. A bad ignition coil
   Dirty transmission fluid
2. A missing gas cap
   An oil pump failure

There are three main problems that could cause stalling while your car's engine is running -- it's a loss of either air, fuel or electricity. Stalling while you're driving -- in particular when you're accelerating, is often due to faulty ignition components such as a bad ignition coil.

1. A thick, acrid burning smell
   A sweet smell, like maple syrup
2. A sulfury smell, like rotten eggs
   A sharp smell, like burning toast

First things first when you're dealing with engine oil -- check the dipstick to see if you're running low on fluid. If that's not the case, engine oil may be leaking into the engine block or into the exhaust manifold, causing that acrid burning oil odor.

1. There's free play in the ball joints.
   There's free play in the steering box.
2. There's free play in the tie rods.
   All of these are possible reasons.

"Excessive play" in your car's steering system means your steering wheel rotates excessively -- more than 1 1/ 2" -- without causing the front wheels to move. What to look for when diagnosing the problem? Ball joints that wiggle in their sockets, loose or worn tie rods, or even a steering rack that's loose on its frame can all cause the problem.

1. Engine oil
   Gasoline
2. Windshield wiper fluid
   Accumulated water

A dark brown and slippery fluid with a bit of a burned smell about it is almost certainly engine oil. You can easily check if the oil pan plug is properly in place and that the oil filter is secured, but the problem may be due to a cracked oil pan or faulty engine valves.

1. Air conditioning won't run.
   Car won't start, or stalls often.
2. Can't shift gears.
   There's a dull, grinding noise in the trunk.

The dashboard fuel indicator light will let you know when your car is running on gas reserves -- but that could take you as far as 25 miles depending on your car and how you drive. When gas levels are very low, look for problems like your car not starting, or stalling a lot if it does run.

1. A clunking noise while braking
   A high-pitched sound that continues after the engine's off
2. A sizzling noise coming from under the hood
   A ticking noise coming from the engine

Often it's too late; your timing belt is broken. But if you listen closely, you can identify the problem before that happens. For instance, what may begin with a high-pitched squeal as the belt shows some wear and tear will end with ticking noises coming from inside the engine -- and a car that won't start, if not addressed.

1. It's no big deal.
   It needs to be checked by a mechanic.
2. Pull over immediately and call a tow truck.
   The light only comes on when the bag deploys.

From a worn-out airbag clock spring to a corroded control module -- or even a low car battery, there are a lot of different reasons a car's airbag light may illuminate. It could be no big deal, but it may also mean your airbags won't deploy if you have an accident -- get it checked out.

1. It's using less fuel than it should.
   It's using more fuel than it should.
2. It's using the wrong type of fuel.
   It's using the wrong type of engine oil.

A car that's running "lean" is running on less fuel than it should be, primarily because fuel in the ignition chamber is being ignited with either too little fuel or too much air in the mixture. The culprits? It could be a sign of a dirty mass air flow sensor, a damaged fuel injector or a damaged oxygen sensor.

1. Clean the engine.
   Replace the spark plugs.
2. Replace the transmission.
   Siphon and replace the entirety of gas in the tank.

From reduced fuel economy to a rusted fuel system, water in the fuel tank can be costly. The best thing you can do when water has gotten into your car's gas tank is to siphon out the "bad gas" currently in the tank. Depending on just how much water was in the tank, allow the tank to dry out before refilling it with fuel to prevent rusting.

1. The Check Engine Light (CEL)
   The Electric Power Steering (EPS) Warning Light
2. The Engine Temperature Warning Light
   The Fuel Indicator Symbol

Whether the illuminated CEL blinks or remains constantly lit up, it can tell you a lot about the problem your car is having. While a steady, not blinking, light means you may or may not notice some deterioration in performance, it indicates there's a problem but probably not an emergency -- in fact, it could be anything from tightening your gas cap to avoid setting off a fuel vapor leak sensor to timing or transmission issues.

1. A faulty water pump or thermostat
   A leaking hose
2. A broken fan belt
   All of these can cause the problem.

There are lots of things that can cause an engine to overheat. Everything from leaky hoses to worn belts to a bad water pump or thermostat -- or even an electrical problem -- could be at fault. Typically, you'll need to wait about 30 minutes for your car's engine to cool down enough for safe handling.

1. Dime
   Silver dollar
2. Nickel
   Penny

The penny test is a way of evaluating tread depth on your car's tires. It works like this: Place a penny with Lincoln’s head upside down into the groove between the tread. If you can't see the top of Lincoln's head, then you're in the clear -- that tread is at least 2/32-inch deep (at least at that location on the tire). You can also use a quarter to do this test, or look at the treadwear indicator bar on each tire.

1. Call a repair shop.
   Call a tow truck.
2. Call your mechanic.
   Exchange car insurance information.

As many as 30 percent of all car accidents in the U.S. are rear impact fender benders. If you have one, you'll want to exchange, at the minimum, your full name, address, and phone number, along with your car insurance information -- and that should include your insurance company’s name, phone number and your policy number. Record license plate numbers and the makes and models of the cars involved. Also take down the names and badge numbers of any responding law enforcement, as well as the names of anyone who may have witnessed the accident.

1. Bad oxygen sensors
   Dirty air filters
2. Incorrect tire pressure
   All of these problems can cause it.

Aside from your own bad driving habits, there are several reasons you may find your car isn't as fuel efficient as it used to be, or should be. Look at three simple causes first, including tire pressure, air filters and oxygen sensors -- all of which can cause a drop.