Auto Loans

Navigating a Used Car Inspection: The Complete Checklist

Editorial Note: The content of this article is based on the author’s opinions and recommendations alone. It may not have been previewed, commissioned or otherwise endorsed by any of our network partners.

There are lots of reasons to choose a used car rather than a new car, and a savings of hundreds, even thousands, is one of them. But there are risks, too. Performing a used car inspection yourself or getting a mechanic to help you will raise any red flags and help you avoid buying a lemon. This used car inspection guide will tell you how to inspect a used car yourself. It also includes a used car inspection checklist that you can take with you.

The importance of doing a used car inspection
Make a used car inspection checklist before you start shopping
What to bring when inspecting a car
Used car inspection checklist
Diagnostic scan
Under the hood
The car’s interior
The car’s exterior
During the test drive

The importance of doing a used car inspection

The seller of your potential new-to-you vehicle doesn’t have to be a lying sleazeball for the car to have problems. Maybe they’re an honest person and don’t know the transmission will give out 5 miles after you buy it. Or they could be skeevy and clear all the warning lights on the dashboard, which promptly light up again an hour after you buy it.

Whatever the character of the seller, you should inspect the car for red flags and, if it passes, take it to a professional mechanic for a more thorough inspection. That way, you won’t waste a mechanic’s time — and your money — on an obvious clunker.

If this is your first time buying a car (or your third and you want a refresher), you could check out the first-time car buyer’s guide.

Make a used car inspection checklist before you start shopping

Look up a potential car model online before you see it. First, do a general search in which you include the year, make, model and trim, if you can, along with the words “common problems” in your search. You may find out that particular type of car is known for going 300,000 miles with little issue or you may find that the engine tends to catch fire after 100,000 miles.

If there are no large warning signs that extinguish your interest, next look up the car’s value in a National Automobile Dealers Association (NADA) guide or Kelley Blue Book (KBB). Both will take into account the car’s location and condition (good, fair, poor) and from whom you’re getting the car — a private seller or a dealership.

If you plan to finance the car, here’s how to get the best deal on a car loan and some news on the best auto loan rates in 2018. Compare loan offers from your bank, as well as credit unions and online lenders. You’re more likely to get a better loan if you shop around. And, don’t worry, it does not hurt your credit to apply to multiple lenders within a 14-day window any more than it does to apply to one. Consider shopping for an auto loan on LendingTree as you could get up to five potential car loan offers from lenders by filling out one online form, instead of filling out five loan applications for separate lenders.

What to bring when inspecting a car

Print out your research and take it with you. This serves a few purposes:

  • You could check off the common problems for the car as you inspect it. See below for examples of obvious no-nos.
  • The official car value printout can be a tool in price negotiation if everything goes well.
  • It’s harder to forget specific questions to ask, especially if you’re looking at multiple vehicles.

If the seller priced the car way under value — be careful. The vehicle may have major problems or it may be a scam. (You can read about how to avoid Craigslist car scams.)

Used car inspection checklist

Remember, once the car passes your initial inspection, it’s still a good idea to have it inspected by a professional mechanic if you’re getting it from a dealership — and an extremely good idea if you’re getting it from a private seller.

Your local oil change place may not offer full mechanical auto safety inspections, so call ahead to ask if it provides that service and for how much. Many places are friendly and willing to help. But before then, here are a few things you can check out for yourself:

Check out our full used car inspection checklist here.

Diagnostic scan

The first thing many mechanics will do when looking at a car for the first time is run a diagnostic scan. There’s little point in popping the hood and test-driving, only to find out the car has a major electrical problem. It’s one of the fastest and easiest ways to get a lot of information on the car.

What it does. It’s a tool that scans the car and reports any problems it may have. For example, if the check engine light is on, the scanner should be able to tell you which part is bad or what needs attention. You can then look up how much a repair costs online and ask the seller to deduct that amount from the price.

How to check it. A free way to get a scan is to ask the seller to meet you at an auto parts shop, such as AutoZone or O’Reilly Auto Parts, where an employee could run the test in the parking lot. You could also buy a scanner for less than $20 online or at the store and follow the directions on how to use it yourself when you first go to look at the car.

Red flags. If the scanner reports a dozen problems or more, walk away. It’s probably not worth fixing. If the scanner doesn’t give any warnings but says “not ready” or “pending” on many items, walk away. Each item should say either “OK” or “fail.” And if the one code the scanner does give you means “all codes were cleared,” that’s not good. Some skeevy sellers manually clear all the warning codes to hide major problems, and you would have to drive the car for a while to let the warning lights reset. If this does happen to you, you might be able to get your money back by following the lemon law in your state.

Why it’s important. A car can look fine and drive well, but a diagnostic scan can reveal major problems. The scan can tell you about problems before they can start affecting how the car works so that you can replace a part before you break down on the side of the road — or not buy a $2,000 car that needs $4,000 in repairs.

Under the hood

If the diagnostic scan goes well, pop the hood and take a peek at the following things.

Belts. Look at the belts in the engine. Are they frayed? The belts themselves are usually cheap ($20), but extreme wear on them signifies the engine is old and maybe wasn’t taken care of as the owner didn’t bother to do a cheap fix for maintenance.

Oil. Pull the oil dipstick to check the oil. The oil level should be up to the fill mark. If it’s very low, that’s not a good sign. Look at the color and consistency, and rub a bit between your fingers. You’re better off not getting the car if the oil:

  • Is dark, sludgy and feels gritty. That means the oil should have been replaced a while ago and the owner probably doesn’t change it often. Infrequent oil changes can damage the engine.
  • Has water in it. This might cause the oil to look like chocolate milk, have froth or appear blotchy. If there is water, that means something is leaking and the oil hasn’t been able to do its job preventing engine damage.
  • Has metal flecks in it. That means something is breaking, the oil hasn’t been changed in a super long time or the engine is on its last legs.

Transmission. There may not be an easy way to check the transmission as some of the newer cars have sealed transmissions, in which case you would need to raise the car and take out a wrench to check it. But if it is not sealed, it should be easily accessible, similar to the engine oil. The transmission fluid should be a clear red color and have no grit or anything floating in it. If it is more brown than red, smells burnt or has gunk in it, that’s not a good sign.

Coolant/antifreeze. This both keeps the engine from overheating and from freezing. There should be a reservoir easily seen with a cap you can twist off to peer inside. The fluid should be a clear neon color, usually green, depending on the brand. It should not be foggy, brown or have anything floating in it. This would mean the liquid hasn’t been able to do its job and the engine may be damaged.

The car’s interior

When you’re in the car, push a few buttons and turn some knobs to test what works.

Air conditioning and heat. You might not think to blast the AC if you’re looking at a car during the winter, but make sure you to test it anyway lest you regret it come August. Blast both the AC and the heat to see if you’ll be able to cool down in the summer and get toasty warm in the winter.

Radio. Turn up the volume! Play both the AM and the FM settings, scrolling the channels to make sure you get reception. If it has a CD player, test it out if you can.

Adjustments. Move the car’s seats and the rearview mirrors. Change the steering wheel height to make sure you can reach the pedals comfortably and see everything. Buckle the seat belt and adjust as needed to make sure it goes across your sternum and doesn’t choke you.

Technology. If the car has a tech package, test out the safety features. Put the car in reverse to see if the backup camera works. To see if the blind spot sensor functions correctly, have the owner or a friend stand in your blind spots on the right and left sides of the car while you put on the turn signal. Press the touch screen and see if the right selections come up.

The car’s exterior

Short of taking apart the engine or crawling under the vehicle, there are a few things you can do to check the heart of what makes the vehicle go and supports the driver’s seat.

Exhaust. Looking at the color of the air that comes out of the exhaust is a good way to check for engine health. Have the owner or a friend turn on the car and rev the engine while you stand behind the vehicle and watch the exhaust pipe.

If some water vapor or steam comes out when the car first turns on, that is completely normal, especially if the weather is cold. But here’s what you don’t want to see:

  • Blue smoke: That may be a sign the car is burning oil and is usually extremely expensive to repair.
  • White smoke (actual smoke, not some water vapor, which is normal): The car could be burning antifreeze/coolant, water or transmission fluid. This could mean anything from a small, easily repaired crack in the antifreeze/coolant container to a cracked engine block.
  • Black or gray smoke: The car is burning more fuel than it should and you’ll probably have to replace the oxygen sensors. Oxygen sensors tell the engine how much fuel and oxygen to mix. If they don’t work, you’ll burn more gas or diesel than necessary, which is bad for your fuel efficiency and bad for the engine in the long run.

You should do this check twice: once when the engine is cold and again when the engine is hot. An engine is considered “cold” when it hasn’t been running for a while and “hot” when it’s been on and warmed up.

Tires. Looking at the depth of the tread on the tires is a time-tested maneuver. But don’t poke a finger or a penny between the tread lines closest to you. Do look for signs of suspension problems, look at the tread on the whole width of the tire. If it’s hard to see, turn the steering wheel sharply to one side so that the entire tire width is visible. If the tread is worn down unevenly, the car probably has a suspension issue, which could lead to a bumpy ride and safety problems.

Depending on the car, it could be an inexpensive fix or a very expensive one. A mechanic’s inspection and repair quote will let you know.

During the test drive

If the car’s passed your inspection so far, take it for a test drive. Go beyond a few circles in the parking lot or a cruise around the block. Ask the owner or salesperson for permission to take it over some potholes and speed bumps and on the freeway.

  • Listen. Any unusual noise, hissing, knocking, pinging or squeaking should all be warning flags.
  • Accelerate quickly. Get up to the speed limit in a short amount of time to make sure it accelerates well. A perfect place would be an interstate on-ramp.
  • Brake hard. Again, warn the owner or salesperson ahead of time and make sure there’s absolutely no one around that you could hit or who could hit you, but jam on the brakes. It’s a good test of what would happen in an emergency. The anti-lock brake system should engage and you should come to a smooth stop.
  • Turn sharply. Turn the steering wheel all the way to the left and right to make sure the car will go where you want it to without complaint.
  • Smell. Don’t forget to pay attention to your nose. If the interior of the car’s cabin smells moldy, it may not be watertight. If something smells like it’s burning, it probably is.

The bottom line

All the fluids you check should be smooth, not gritty. Nothing should smell burnt, wet or moldy. The exhaust should be clear. There shouldn’t be squeaks or bangs. And if you have any questions, take it to an independent mechanic. If the owner or car dealership doesn’t allow you to take it for an independent inspection, that in itself is a red flag and you might be better off looking at a different vehicle.


Compare Auto Loan Offers