How to inspect a used car - illustrated used car checklist

Used cars might have have hidden problems that aren't obvious during a test-drive. We hope this guide will help you recognize signs of potential problems and make a more informed decision.

We recommend having the vehicle inspected by a knowledgeable mechanic before signing the deal. There are many things that can only be properly inspected when the car is lifted on the hoist. For example, many used car buyers arrange to have the pre-purchase inspection done a local dealer specialized in that brand.

This car should be avoided

Start with the quick walk-around. rust spots like this one should tell you to avoid this car. Why? Because major components underneath the car could be rusted too, making the vehicle unsafe. Look for example, at these brake lines, or this subframe (engine cradle).

Blue smoke from the exhaust

You can catch some of the early engine problems when the engine is started cold, after the car sat for a while. If the engine rattles at a start-up or you can see a blue smoke like in the photo, even if it's a small puff, avoid a car.

Cars with AT, Airbag (SRS), 4WD and other warning light staying on should also be avoided

Have a look inside. Most dealers detail cars before showing, but steer clear of the car if it looks really dirty. How do the steering wheel, driver's seat and the inner door handle look like? Are they badly worn? Does it smell bad inside? Bad smells inside the car are difficult to get rid of.

Are there any warning lights staying on? This car has the SRS (airbag) light on, it will be expensive to repair, this car should be avoided.

Check the reflection to see if all panels are lined up and to catch signs of body repairs.

Look at the reflection of the side of the car. It can tell you if all panels are lined up and you can catch signs of body repairs. This car looks OK: panels are lined up and the paint texture looks uniform on all panels. Click on the photo to see a larger image.

Look closely at this rear door, click to see the larger view.

The rear door of this car shows signs of body repairs. Tap on the photo to see. Not only the texture is uneven, you can see some lines right above the moulding. Those lines were left from sanding. Sanding is done to smooth out the auto body filler and the primer to prepare the surface for painting.

This door has been damaged. It might have been a minor damage, but how can you tell if it was done right and the paint won't peel off in a year or two? Read more: How to inspect a car body

This chip may cause the glass to start cracking further.

Look carefully at the windshield. Note any chips, scratches or other damage. Some chips and star cracks, if large enough, can cause the vehicle to fail a safety inspection. Replacing the windshield costs from $320 to $1000. If there is a front-sensing camera or sensor attached to the windshield, it might also need a calibration after windshield replacement.

This scratch on the windshield will cause glare at night

This scratch was made by the metal part of the broken windshield wiper. This scratch will produce glare when driving at night. Similar scratches can be made by sand caught under the wiper blades.

Some aftermarket low-profile rims bent easily.

Check the rims. Some aftermarket alloy rims, especially low-profile ones like this one in the photo can bend after hitting even a small pothole. This rim is bent on the outside, but often the damaged spot is on the inside. The only way to catch this is during a pre-purchase inspection when the car is lifted on the hoist. A symptom of a bent rim is a vibration felt on the highway, although it's not always easy to detect during a short test drive. Replacing a rim like this could be expensive. Original-equipment alloy rims are stronger, but they too can get bent.

Cracks on the sidewall of the tire

Check the tires. Do they look worn out? Do they have cuts or other damage? This tire in the photo shows cracks in the sidewall, it will need to be replaced even if the tread is still OK. Are all the tires of a reputable brand or a no-name product? Do all tires show even wear? Uneven tire wear indicates problems with the suspension or wheel alignment.

This tire has a bulge or bubble on the sidewall. It's unsafe and must be replaced.

This tire has a bulge on the sidewall and must be replaced. A bulge is not repairable and the tire with the damage like this is unsafe to drive.

New versus worn-out tire

New tires have tread depth from 10/32" to 11/32". The tire in the top image is almost new. New tires like this can last up to 50,000 miles.

The tire in the lower photo is worn out to 4/32", which means this car will need new tires soon. Look at the wear indicator bar. A set of tires, depending on the size and brand costs from $400 to $1200. Low-profile 18" and larger tires are always more expensive. You can look up the price at TireRack.com.

Test if both key fobs work. Typically a new car comes with two or three keys or key fobs; ask how many come with the car.

Check the condition of the seats, look for burnt marks and other damage. Minor damage can be repaired, ask if the dealer can arrange for the repairs. Check the condition of the seat belts.

Rear wiper is another part that often has problems in older cars. Test all wipers and washer functions.

Test power windows, power locks and mirrors. Window regulator problems are common in many older cars. Sometimes a window goes down well, but goes up very slow or crooked.

Problems with heated seats are very common and a heated element could be quite expensive to replace. Test both seats.

Check all the controls, including the audio system. If the car has a CD player or AUX / USB input, check if it works.

Make sure to test the air conditioner; air conditioner problems are common in used cars. With the engine running, turn the A/C on. You should feel cold air coming from the vents soon after the A/C is turned on.
Test all the heater fan speed settings; it's a common problem when the heater fan works only at high speed settings. Watch out for musty smell from the vents. A burnt oil smell from the vents indicate possible oil leaks in the engine compartment. An antifreeze smell is a sign of a problem too.

If the vehicle has the rear heater/AC controls, make sure everything works there too.

If a car has been flooded, it's more likely to develop many problems in the future. Modern cars have many electronic components under the carpet and around the foot wells that can get damaged if submerged under water.

This car in the photo has been flooded during a heavy rain. You still can see the water level mark in the speaker cover. Look for signs of moisture under the carpet. Check the trunk and the spare tire well for signs of water damage. A history report can also reveal flood damage. Be suspicious if the history report indicates that the car came from the flood area.

Check if the car has the spare tire and the jack. If the wheels have wheel locks installed, make sure there is the key for the wheel locks.

Coolant leak from a crack in the radiator.

Minor leaks are fairly common in high-mileage cars, but all else being equal, you are better off with the car that has no leaks at all. In addition, leaks (coolant leaks especially) could point to more serious problems.

This car, for example, has a coolant leak from a small crack in the radiator. The engine runs fine, however, upon further mechanical inspection, we found that the head gasket started leaking in this car. A head gasket repair is very expensive. Look for leaks under the car; the only thing that should be dripping from under the car is water from the air conditioner drain tube when the A/C is running. The A/C drain tube is typically located under the passenger side of the firewall. Any other leak (coolant, engine oil, transmission fluid, etc.) points to a problem. The smell of burnt oil or antifreeze under the hood is another indication of possible leaks.

This car needs a battery and a battery terminal to be replaced.

The battery terminal in this car is badly corroded. Not only this car needs a new battery and a new battery terminal, this suggests that this car hasn't been serviced regularly, otherwise this problem would have been fixed during one of the regular services.

Here is another example: this bolt clearly looks out of place in this car (click on the image to see larger view). There supposed to be an engine mount in this place, but it's missing in this Toyota. This obviously doesn't look like a high-quality repair.

If you are uncomfortable with these these tests, leave them for your mechanic. Make sure the engine is off and the parking brake is applied. Find the engine oil dipstick (usually it has a bright handle that says" Engine Oil." Pull the dipstick out and check the oil level and condition. If the oil looks very dirty and the oil level is very low, it means that either the engine consumes oil, or it has been poorly maintained. Check the condition of the dipstick itself; if it's covered with black deposits, it's also a sign of poor maintenance.

With the engine off, open the oil filler cap and look inside the engine; use your flashlight. If the internal engine parts that you can see are covered with thick black deposits, it's also an indication of poor engine condition.

If you can find the transmission fluid dipstick (not all cars have one), check the transmission fluid condition. To see better, drop some fluid on a white paper towel. Transmission fluid should be clean and transparent. Very dirty transmission fluid that has a burnt smell is a sign of excessive transmission wear.