Rapid Fire Quiz: Car Symptoms and Solutions Edition

AUTO

Dave Davis

7 Min Quiz

Image: Pixabay by Peter H

About This Quiz

We take our cars and trucks for granted while everything is working the way it should. Because the automobile is an extremely complex machine, however, with little tolerance for error, problems can quickly capture our attention. While novice — or uneducated — drivers might wonder what's making that knocking sound, however, those experienced in the ways of the internal combustion engine can pinpoint the problem and come up with a solution (Hint: Knocking sounds generally aren't good signs). 

So, which are you? Are you the person people come to when they have automotive questions or are you the kind who immediately looks to a higher mechanical power for answers? This quiz will test your knowledge and deductive powers. Those in the know will be able to quickly make their way through this without breaking a sweat. Those whose automotive knowledge is lacking, however, are about to learn some valuable (yet free) lessons.

Every problem has a solution. Sometimes those solutions are simple, easy and cheap. Sometimes, well, you might have to shift some things around in your budget to start things back up. But knowing what the problem is, or could be, is the first step in getting the matter corrected and getting you back out on the road. 

We think you've got what it takes to ace this quiz. Prove us right by showing us that you know what to look for (and listen for and, in some cases, smell for) to diagnose an automotive problem. Put your mechanic cap on, and let's go!

Which of these problems could cause your car to stall?

Many things have to go right for your car to run, and the vast majority of the time, they do. When something goes wrong, however, the engine will run rough, not run at all or stall out while running. You're going to need more clues to get it back to good!

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It's been harder to get your manual transmission into gear, but today it finally became impossible. What could be the issue?

When the clutch plate is worn, it can become increasingly difficult to shift into different gears in a car with manual transmission. The clutch sees a lot of mechanical pressure over its lifespan and will need to be changed after enough miles are put on it.

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You hear a grinding sound when you apply the brakes. Which of these parts probably needs replacing?

That grinding sound you hear when you brake means that your brake pads are worn and need to be replaced. Don't put it off! The longer you go with substandard pads, the more damage you could do to other parts of the braking system, which means a higher bill at the garage.

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When it goes bad, which of these can cause your engine to overheat?

The thermostat in your car is a valve that keeps coolant from flowing until the engine reaches its optimal running temperature. It then SHOULD open and let the coolant do its job. If the thermostat gets stuck, your engine might not get coolant, and things will quickly start to heat up.

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Which of these could be a sign of a bad EGR valve?

The exhaust gas recirculation (EGR) valve works by taking some of the emissions generated by the engine and recirculating them through the combustion chamber, which reduces pollution while lowering temperatures in the cylinder. When this valve goes bad, the above symptoms will appear (your car will also probably fail an emissions test).

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When you let go of the steering wheel while moving (slowly!), the vehicle veers to one side. What's the probable cause?

The vehicle's suspension needs to be aligned every so often — normal wear and tear, as well as potholes and other road hazards, can misalign the car's wheels — so that the car tracks true. If you notice it's pulling to one side, misalignment is usually the reason.

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When you start to hear a chirping sound coming from your vehicle, what should you suspect?

If you hear a chirping sound when your vehicle changes speed, check to see if you can detect if it's coming from one of the wheels. If so, you've got a wheel bearing going bad and need to have it checked out. If it fails, it could affect the way your vehicle handles, to say the least — that wheel could lock up or come off the car completely.

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What can cause a knocking sound that gets louder as the engine's RPMs rise?

If you hear a knocking sound that gets louder the more your engine is strained, get the checkbook ready; you've probably got a problem with a piston or its connecting rod assembly. It's a major problem, and you need to get it taken care of before it becomes a disastrous problem.

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Which of these will happen when your car's oxygen sensor goes bad?

The oxygen sensor, which detects how much oxygen is in your car's exhaust, tells the car's computer if there needs to be more or less fuel in the air/fuel mix going into the cylinders. When this sensor goes bad, fuel economy will drop and your car might run rougher.

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Because we know you check your oil regularly, what color should the oil be on the dipstick?

Oil will darken as it ages over time, starting out as golden, then golden brown. If left in too long, it will eventually turn black, which tells you it's dirty and needs to be changed. Visible metal flakes in your oil are a sign that your car needs to be serviced immediately

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The Manifold Absolute Pressure (MAP) sensor will cause what to happen when it fails?

When working properly, the Manifold Absolute Pressure (MAP) sensor tells the vehicle's computer how hard the engine is working by measuring the air pressure in the intake manifold. If this sensor starts giving the computer false readings, fuel control and emissions are thrown into disarray.

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There's dark smoke coming out of the tailpipe and you swear you smell brimstone. What's going on?

We can't tell if your car is possessed from here, but if you start smelling a "rotten egg" scent and there's black smoke coming from the tailpipe, these are signs that the catalytic converter is about to give up the ghost. Get to a mechanic (and then a priest if you're convinced that a possession is taking place).

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When the engine misfires, isn't getting the power it needs and finally just won't start, which of these could be the problem?

Like all filters, the fuel filter can become dirty and/or clogged over time. When this happens, the engine won't get the fuel it needs, which will first become apparent when the engine is put under load (accelerating). If the filter becomes clogged, it can completely block the flow of fuel and the car won't start.

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Brrr! It's a cold day and the defroster isn't working. Which of these could be the culprit?

The heater core produces heat for both the defroster and the cabin heat system by taking warmth from the hot coolant flowing through the engine. If there's not enough coolant, the heater core won't heat, and the defroster won't function properly.

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When a car is blowing thick white smoke out of its tailpipe, what could this be a sign of?

Bad news, partner. If your car is blowing thick white smoke out of the tailpipe, it could be a sign that the head gasket — which separates the cylinder head from the engine block — has given way. Get it taken care of quickly because it means things are mixing in the engine that should be separate, and that will kill your engine quickly.

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A dirty air filter can cause which of these symptoms?

All the air that goes into your engine to combine with fuel for the internal combustion process goes through the air filter. If the filter gets dirty, that affects the amount of air — and fuel — that goes into the cylinder to be combusted. In most cars, a dirty filter is easy to check and easy to replace.

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When you apply the brakes, you feel a vibration running through the pedal. What does this tell you?

When you feel a vibration running through the brake pedal, this generally means that the brake rotor (also called the disc) has warped. The brake pads make contact with the disc, and the friction slows and stops the vehicle. The rotor can sometimes be shaved back to flat if it's not too warped, or it may need to be replaced.

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You've ignored the oil leak in your engine and the warning light on your dash. What's about to happen?

Your engine is a symphony of moving parts, and without oil, these parts will start to rub together, grinding each other down and causing heat to build. If you run an engine without oil (or even the proper amount of oil), it will seize, and you'll be looking for a new one.

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You're driving along and all of a sudden, the A/C quits and your car now steers like a tank. What just happened?

The serpentine belt runs several systems under the hood of your car, including the power steering pump, the A/C and the alternator. When it breaks, a great many things go wrong simultaneously. You'll need to get it repaired, and just hope that nothing was damaged when the belt gave way.

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The smell of syrup is usually a good thing, but not when it's coming from your car. What's the cause of that sweet smell?

When the ethylene glycol from your car's antifreeze comes into contact with a hot surface, the smell the cooking coolant leaves behind might smell like syrup. That scent means you've got a leak somewhere in the cooling system.

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When your car is at idle, it sounds like it's about to run away. What could cause a high idle?

When there's a leak in a vacuum hose or fitting, too much air could be entering the internal combustion process. This can cause the fuel/air mix to be out of balance and will affect how the engine runs.

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Which of these conditions can affect the pressure in your tires?

When the temperature falls, tire pressure can be affected (the cold causes the gas inside the tire to become denser and more compressed). If you get a "low tire" light on your dash, it might go away once the tire warms up and the gas expands. If not, check the pressure; you might have a leak in one of the tires.

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You notice that the center of your tire is wearing excessively. What could be causing that?

When the center of the tire is wearing faster than the rest of the tread, check your tire pressure (and the recommended pressure). If it's overinflated, you will ride on the center of the tread, and the tire will wear unevenly.

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This is a strange problem. The air blower in the cabin will work on "high" but not at lower speeds. What could cause this?

If the blower won't work at any speed, it's probably a fuse. If it will only work on high, however, the problem is most likely a bad blower motor relay. The relay, when working, limits the voltage going to the motor to make it run at lower speeds. When the relay goes bad, the motor bypasses it on "high" but won't work at lower speeds.

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Your "Check Engine" light is flashing, there's a loss of power and there are noises coming from the engine. What gives?

The timing belt connects the camshaft to the crankshaft and keeps them in sync. When the belt gets worn, the engine starts to exhibit these symptoms. Get the belt changed before it breaks and strands you on the side of the road with a damaged engine.

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You turn the car off, but it doesn't seem to want to stop. What can cause a car to "diesel"?

When a car's engine is running on too rich of a mix, meaning there's too much fuel in the fuel/air combination, carbon can build up in the cylinders. When heated, this carbon can ignite the mix left in the chamber and keep the engine going for a bit after you've turned it off.

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When you take your spark plugs out to change, you notice the old ones appear light tan. What does this tell you?

You can tell a lot about how the engine is operating by looking at the condition of the spark plugs. In normal operation, the electrode-end of the plug will be a light tan or gray, which tells you that everything seems to be going fine. If the plug is burned, wet, has deposits or shows other unusual conditions, it's a sign that something needs to be addressed.

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Which of these is the most common cause of your car's Evaporative Emission Control System to throw an error?

The Evaporative Emission Control System (EVAP) on your car is designed to detect fuel vapor leaks in your car's fuel system. The onboard diagnostic system (OBD) will show an error in the event of a fuel pressure leak, and one of the things it might point to is a loose gas cap.

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You're driving along and suddenly something smells like burning carpet. What's the first thing to check?

A burning carpet smell generally means that a brake is engaged while the car is in motion. The first thing to check is to see if you're driving with the emergency brake engaged (hey, no judgments; we've all done it). If that's not the case, have your brakes looked at because the problem could be more severe.

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Which of these symptoms will tell you it's time for a new muffler?

Your car tries to tell you what's going on with it through certain subtle signs — except the muffler. When the muffler goes, your car will start to roar, and there's nothing subtle about it. Get it fixed before the neighbors start to complain.

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Which of these symptoms could be caused by a bad alternator?

The alternator has many ways to tell you that something isn't right — the headlights will flicker and dim, the power windows will become sluggish, the battery light will light up on the dashboard, and, eventually, the battery will die.

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The engine is misfiring, idling rough, won't accelerate easily and is drinking gas. What could be the culprit?

Your spark plugs provide the fire to ignite the internal combustion process in each cylinder. When they're worn, that spark won't be as strong, or it might stop altogether. This causes the above symptoms. It's an easy process to change them out in most cars.

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Your car hesitates when you accelerate, surges in speed at times and is hard to start. What could be the issue?

This could be a tough one to diagnose, but all those symptoms could be due to getting a bad batch of gasoline from your last fill up. A car's engine needs a very precise type of fuel to operate, and if water has entered the gas for some reason, or the gas has oxidized, you'll notice the results.

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You notice that your car is making an odd humming sound when in neutral, and the "Check Engine" light is on. What should you suspect?

If you hear a new humming sound when the vehicle is in neutral, this could be the sound of a transmission in trouble. It could signal that the transmission fluid is breaking down and not lubricating the moving parts the way it should. It's time to get to a mechanic before this nuisance turns into a crisis!

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You've got intermittent white smoke coming out of the tailpipe, a rough idle and a lack of power. The spark plugs seem fine. What else could it be?

The spark plugs fire with as much as 75,000 volts, which is a much higher voltage than the battery produces. The ignition coils take the energy provided by the battery and step up the voltage to something the plugs can use. If a coil goes bad, however, this process starts to break down.

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What can happen if you mix different types of radiator antifreeze?

Mixing different types of antifreeze (orange and green, most commonly) can cause a chemical reaction that makes the substances turn into a gel. Since a gel won't flow like liquid antifreeze is supposed to, you're about to experience some engine overheating.

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If your car starts to emit the subtle smell of a locker room in the passenger compartment, what could be the issue?

When your car's cabin starts to take on the odor of a locker room, it means there's mold in the evaporator of the air conditioning system. Run the fan with the vents open and the A/C off and see if it clears up. If that doesn't work, you might have to have the system cleaned. Your back seat also probably needs to be cleaned out, but that's a whole other issue.

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Your high-mileage car is running rough and every now and then, it stalls when idling. What's the problem?

Worn piston rings, a leaky head gasket, bad valves, worn-out camshaft lobes and other problems can cause a lack of compression in the cylinder when the air/fuel mix is pressurized before the power phase in the four-stroke engine. A compression test will tell the mechanic — and you — where they problem lies.

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You put the key into the ignition, try to turn it and ... nothing! The key won't turn at all! What's the first thing to check?

If an automatic car isn't in park or neutral, the system is designed to not allow the key to move. Put the car's shifter into one of those positions and try again. If that's not it, there could be a problem with the key or the ignition cylinder.

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Which of these could be a cause of "jerky" acceleration (and by that, we mean "uneven," not driving like a jerk)?

The cable that connects the accelerator to the throttle can become worn or stretched over time, causing hesitation when accelerating or uneven performance. If this is the problem, replace the cable because if it breaks, you'll be going nowhere fast.

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