The Ultimate Car Symptoms and Solutions Quiz

Maria Trimarchi

What color fluid would you find on the ground under your car if there's an oil leak?

An oil spot under your car will be brown fluid. Most of the time, it'll be because of wear-and-tear on gaskets, seals, and connections -- and don't forget to check oil pan seals, which are under the car.

A faulty thermostat can be a common reason for a car's engine to overheat.

The thermostat's job is to block the flow of coolant to the radiator until the engine has warmed up. A broken thermostat won't let coolant reach a hot engine, thus causing it to overheat.

Which is not one of the three things your car's engine needs to start?

For your car's engine to start, it needs to have good air/fuel mixture, compression, and a spark (that's the ignition).

What does it mean to "throw a rod"?

"Throwing a rod" means a connecting rod, which connects a piston and the crankshaft, has broken.

Your steering wheel is vibrating and you can feel your car shake, especially when you're idling, and it might stall at a red light. What's going on?

If your car's engine is shaking so badly you can feel it in both your steering wheel and your seat, there's a misfire problem, including a worn spark plug, a bad spark plug wire or a clogged fuel injector.

Why might your passenger complain of feeling vibrations in the passenger seat?

Excessive engine vibration, usually because of bad motor mounts aren't holding it securely, can be felt on the passenger's side of the car.

What does it indicate if your car's engine oil turns from amber to a foamy, milky white?

Motor oil can be amber to dark brown to almost black depending on how used and dirty it is. But if it's a foamy, milky white, it means that some antifreeze (or water) has contaminated it, and you'll want to look into what could be leaking from the car's cooling system.

Which is the most common symptom of a seized engine?

Although all of these are symptoms your car's engine has or is about to seize, the most common is complete engine failure.

But what if the knocking noise is less of a ping and instead more of a deep hammering noise?

A deep knocking that's more like hammering than pinging is called a "rod knock." This happens from wear-and-tear or damage to the rod bearings -- and it's a fatal engine problem.

You can't start the car, you smell gasoline, and is that a puff of dark smoke that came out of the tailpipe? What could this trio of symptoms indicate?

Together these symptoms usually indicate the car's engine is flooded.

What should you do if your engine is flooded with fuel?

This can happen when the mixture of fuel and air gets off balance, most commonly in cars that have a carburetor instead of fuel injection. The best way to solve it is to let the excess fuel evaporate, so wait as long as you can, and then try to start the engine while holding the gas pedal to the floor -- but don't pump it, because that could be what got you in this predicament to begin with.

You hear a popping sound coming from under your hood, and now it it feels like your engine is hesitating. Which of these might be the problem?

When your car feels sluggish and you can hear popping from under the hood, it could be anything from dirty or damaged spark plugs and spark plug wires to a clogged fuel filter and, possibly, ignition problems or trouble with the car's catalytic converter.

Thick black smoke coming from your car's exhaust pipe can seem alarming. What might cause that?

Black smoke coming from a car's exhaust pipe can happen because the engine is flooded with gasoline, typically by damaged fuel injectors and sensors. Black smoke can also mean a problem with your car's air filter too.

What is white smoke coming out of the exhaust pipe a symptom of?

On a cold morning you may notice white vapor coming from your exhaust pipe. It's normal and stops as soon as your car warms up -- probably no longer than 20 minutes. But, if it's white smoke coming from your car's exhaust pipe, that can be caused by all of these problems.

What kind of fluid leak could cause the color of your car's exhaust to turn blue?

Blue smoke indicates there's a problem with leaking and burning oil.

Why might it smell sweet in the passenger compartment of your car?

A sweet, steamy smell inside your car is a coolant problem, and the engine is overheating.

Which is not a sign your car's engine has a worn piston ring?

Excessive oil consumption as well as poor performance and loss of power are all common symptoms of worn piston rings.

Which piston problem sounds almost like a bell?

"Piston slap," the sound a piston makes when it rocks back and forth inside a cylinder, sounds a lot like a bell.

The mass air flow sensor (MAF) measures the air flowing into the engine, and it figures out how much fuel needs to be injected. How would you know if it's malfunctioning?

You'll know your car's MAF is bad because it can decrease your car's fuel economy by as much as 25 percent.

What is the green or orange sweet-smelling fluid that's left a spot under your car?

Ethylene glycol antifreeze is that green, orange or yellow sweet-smelling fluid. The first symptom of a leak? If you don't notice the indicator lamp, you will notice when your car's engine overheats.

What happens if you accidentally put diesel fuel into a car with a gasoline-powered engine, and then drive home?

Diesel is thicker than gasoline, which means as soon as you started the car, the diesel went to work clogging your gasoline-powered engine's fuel injectors, filters and lines. If your car makes it home and continues to start, you'll feel timing and performance problems before the engine gives up.

You turn your car off, but it continues running. It's not possessed. But why would that happen?

Also called run-on, it mostly happens when you fill up with the wrong octane gas for your car. Both a failing solenoid or an overactive carburetor could also cause the problem.

What is your car's engine lacking if it is surging at highway speeds?

If your engine is surging it's a sign that it's not getting the right fuel mix or enough of it.

Hearing dinner sizzle on the grill is far better than hearing a sizzle under your car's hood. What does it mean if you hear your car's engine sizzling or hissing right after you turn it off?

Sizzling indicates there's a fluid -- engine oil or antifreeze -- leaking onto something hot, like the exhaust manifold.

Knock. Knock. Your engine doesn't want to come in, but it does have something to tell you. What is engine knocking/pinging a sign of?

There are a few reasons, and degrees of severity, for your engine to start pinging or knocking at you. It happens because of a problem with the air-fuel mixture, and could mean: you need to use a different fuel octane, there may be carbon buildup or the spark plugs need replacement. Left unfixed, it can do some serious engine damage.

What could be wrong if your car's gas mileage has been poor lately, and now it's stalling?

Poor gas mileage and stalling, as well as idling rough and, if you listen, a hissing sound from around the engine area under the hood, are symptoms of an engine vacuum leak.

What's causing the clicking noise that gets louder when you rev your engine but disappears at higher speeds?

Clicking noise, also called "chatter," is the sound of your car's valve train, specifically defective hydraulic valve lifters (also known as hydraulic tappets).

Which is not a reason the Check Engine / Malfunction Indicator Light could come on?

The Check Engine Light, also known as the Malfunction Indicator Light, will trigger for a lot of things, including bad catalytic converter, for a dirty air flow sensor, and a loose gas cap, but it won't give you reminders.

What controls your car's performance and drivability, like the engine spark and fuel efficiency?

The engine control module (ECM), also known as the engine control unit (ECU) or powertrain control module) PCM), handles the engine's performance.

Which is the worst case scenario for why your car has low oil pressure?

First, check that your oil level isn't low. Not the problem? It could be oil pressure. If that's not about 10 PSI for every 1,000 RPMs of engine speed, it could be a bad oil pump; if it is, it could be the oil pressure sending unit is on the fritz. But the worst case scenario is worn engine bearings, which means your engine will need to be either rebuilt or replaced.

You're idling at a red light when you hear what sounds like a metallic double knock. What part of the engine could cause that noise?

Faulty piston pins cause engine knocking, but it's a really specific type: a metallic-sounding double knock, usually most noticeable at idle.

Which is not one of the three most common engine problems?

The most common three engine problems are: 1) the engine won't start, 2) Service Engine Soon light comes on and 3) overheating.

The Check Engine Light shouldn't stay on for more than a few seconds after you start your car. What should you do if it starts flashing?

A flashing Check Engine Light means the problem is more serious than a loose gas cap. Check for signs that your car's engine is misfiring, a serious problem that could cause damage to the catalytic converter.

Which is not a reason for a car's engine to seize?

Your car's engine may seize if there's a lack of oil, if there's rust accumulation and if there's a mechanical issue like a loose piston that's become lodged.

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Image: Witthaya Prasongsin / Moment / Getty Images

About This Quiz

So you can drive a car, sure, but can you troubleshoot one?

These days, car technology has developed by leaps and bounds. In comparison to the past, some problems we encounter today don't seem as catastrophic. No matter if you're driving a manual or an automatic transmission, there will still be some basic problems that you will definitely encounter while driving on the road; regardless of the car brand, some problems tend to be universal in nature.

That is why it's smarter to be "in the know" about major features and specific issues that a car could develop from time to time. This also means that as a motorist, we all have to be responsible for the safety and reliability of our vehicle's various mechanisms, both inside and outside. After all, this four-wheeled vehicle -- no matter if it's 2WD or 4WD -- carries not only our things but also our lives. To be safe on the road is always better than to be sorry off the road after a disaster. We know you agree with that!

Do you think you know even the most basic troubleshooting tips and techniques in handling a car? Then let this quiz help you out as a handy reviewer. It's time you get acquainted with these issues, so click away and get started on this quiz!

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