What to look for in a used car

Buying a used car is the classic buyer's-nightmare scenario, a task complicated by infinitely many possible unknown mechanical flaws and the typical intent of the seller to make as much money off the sale as possible, as quickly as possible--in contrast with housing sales, in which the seller does not expect to get the sale finished in a day or two and fully expects the buyer to do a thorough investigation of the house and property before reaching a firm decision, used-car sellers seem to be universally possessed of a mindset that someone can decide they want to buy a car in about 30 seconds.

Knowing what to look for in a used car makes all the difference. It's an experience you want to enter into knowing as much as you can. The knowledge you want to have can be roughly divided into two categories: Mechanical, and legal. Obviously you don't need to be a certified auto mechanic, but having an understanding of the most important mechanical systems to check and how to verify that they're in good working order is useful. But buying a car isn't as simple as making sure it works, paying the seller, and driving away; in almost any part of the world, cars need to be licensed by some governmental authority, and you'll need to know the laws and procedures regarding transfer of vehicle ownership where you live.

There are countless websites devoted to the subject of what you should look for in a used car, so this website is perhaps a little redundant, but I put it up anyway. Other notable sites with similar content include eBay's own guide as well as this one on MSN's autos section. The BBC has a checklist here as part of their larger section on buying a used car. There's also an almost excessively detailed used-car checklist here on Autopedia.


Before you go, do a little background research

Before you even go to meet the seller, do some research to find out about the car(s) that you're going to see. Many models of car are prone to very specific problems. For example, Japanese cars of the 1980s tend to have excellent engines that last just about forever, but their electrical systems like headlight switches tend to be prone to failure. You can go to carsurvey.org and see what comments other people have left on the year, make, and model of the car in question to get an idea for what's most likely to fail.


Check the car's engine block for its general condition. Make sure it's not rusty.

Start the engine and make sure it runs smoothly, without needing a lot of cranking to start or producing a lot of vibration or noise. Push the gas pedal in and out a few times to ramp up the engine speed, and make sure it accelerates quickly without vibrating or hesitating; similarly, when you release the gas pedal, the engine should come smoothly down to idle without stalling (many engines have a harder time slowing back down to idle than speeding up from it).

Check all the accessory belts. Make sure they're in good condition, not torn or frayed, and that they're of appropriate tightness.


Look at the brake discs (if any) and make sure the discs are smooth and clean, not rusting, pitted, or scratched.


Check the body for rust. A common trick employed by used-car buyers is to bring along a small magnet (like a fridge magnet) and tap it against the car's body all the way around the car. If the magnet sticks to the body, you know that the magnet is touching metal. If you find any spot where the magnet won't stick, this suggests that the area has been dented or otherwise damaged at some point, and filled in with plastic body filler.

Tires and wheels

Look at the tires and make a note of the wear pattern on them. If there's any misalignment in the car's suspension, this will often manifest itself in uneven bands of wear on the tires. Of course, you won't be able to observe this if the seller has recently put new tires on the car, so if the car has almost-new tires, this could be a sign that the seller is trying to conceal something. (Or it could just mean they decided to change the tires, which isn't at all unreasonable.)

Don't forget to check the spare tire, too! Make sure it's in good shape and inflated to the proper pressure.

Interior environment

Make sure you can sit comfortably in the driver's seat. If you're tall, you may find that it's hard to sit in the car without your head bumping into the roof. Make sure the seat back can be placed into a comfortable position where you're not leaning too far forward or backward.

Make sure the car doesn't smell bad inside. Check the stains on the carpet and seat covers. Check for rips in the upholstery and roof lining.

Get a big bucket of water, or a hose, and pour it all over the roof of the car; make sure that no water leaks into the interior of the car.


With the engine running, look under the car and see if anything's leaking out, or if there are obvious signs that fluids have been leaking there recently.

Coolant check

Check the coolant in the radiator, and make a note of its color. If it's bright green, like fresh coolant is supposed to be, that's a good sign. If it's somewhat discolored, that can be a warning sign (especially if it's brownish and muddy-looking) indicating that the cooling channels in the engine block are rusting.

Electrical systems

Check the headlights. Make sure they both work and are bright. Check both the low and high beams.

Check the turn signals. This can be easily done by acticating the hazard light switch, which should turn on all the turn signals at once. Also try it with the flip lever, to be sure it works.

Ensure that the brake lights come on when the brake pedal is pressed. It can be helpful to have someone with you to push the brake pedal while you observe the rear of the car.

Make sure the reverse lights (the white illumination lights on the back of the car) turn on when the transmission is put into reverse.

Check the dashboard illumination; make sure it makes all of the dashboard instruments readable.

Check the interior lights of the car; make sure they work.

Test the horn. If the car has those little horn buttons instead of a big horn pad, test each button.

If the car has an anti-theft alarm system, test that too.


If the car has any power-assisted amenities, test them to make sure they all work smoothly. Any of the following, if existent, should be tested: Power windows, power locks, power mirrors, power steering, power brakes, and power sunroof.

Check the heater and air condition (if the car has one) to make sure they blow hot and cold air, respectively.

Test the sound system (if any) and make sure it works.

Road test

If everything thus far looks good, it's time to take the vehicle out for a road test. Ideally you want to be able to take the car through its paces, but if the seller just happens to be in a densely-populated area not near any freeways, you may be stuck with just local city driving. Even so, there are a lot of things you can test in the city.

Make sure the car starts moving quickly from a stop, without hesitation or stalling.

Test the brakes. Make sure the brakes work well under both light braking and hard braking conditions, without squealing, shuddering, or pulling to one side.

Check the cornering. Take the car around a few hard turns, and make sure the steering is responsive and that there are no clunking sounds or vibrations during hard cornering.

Mechanic's inspection

Once you've inspected the car yourself, you should also take it in for inspection by an auto mechanic who you know and trust so they can give you a professional opinion.


In North America, you should check the car with Carfax before you buy. Carfax is a private company that tracks vehicle histories, and will show them to you for US$20. This investment is well worth the cost, given the information that the report shows you: You'll see the car's sale history and all of its emissions tests, including whether it passed or failed them. Each of these records is also accompanied by a date, location, and odometer reading. The Carfax report also tells you whether the car has even been in an accident, stolen, or involved in a flood, as well as whether the car has any liens on it (i.e. if money is still owed on the car). I don't get paid to endorse Carfax, they're simply the industry standard for these kinds of car background checks. Unless the car is being sold for $20, the price you pay to Carfax is probably well worth the peace of mind their report provides.


Know exactly what paperwork your location requires for a legal used-car sales. At a minimum, the seller will need to give you some certificate of transfer stating that s/he is transferring the vehicle to you. In most cases, a few signatures and simple filling in of names and addresses are most of what's required.

Many places now have emissions laws in place requiring used cars to pass a pollution test (often called a "smogging") before the ownership of the car can be transferred. If this applies to your location, make sure the seller has smogged the car and provided you with the correct certification form. Make sure the date of the smogging is still valid, since it typically doesn't last for very long; in some places, the car will need to be smogged within 30 days of the sale, whereas in other places it's 90 days.

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