How to Inspect a Used Car Before You Buy

To inspect a used car, do a slow walkaround, an under hood check and a look underneath in daylight, then have a mechanic scan and road test it before you pay.

Set Up the Visit Right

How you see a car matters as much as what you look at. Ask to see it in daylight, not under lot lights or in the rain. Water on paint hides scratches and dents. Dim light hides mismatched color.

Ask the seller not to start the car before you arrive. A cold engine shows problems that a warm one hides, like a hard start, a rattle that fades, or smoke that clears after a few minutes. Put your hand on the hood when you get there. If it is warm, ask why.

Bring a flashlight, a paper towel, a penny and your phone. Take photos of anything that looks off so you can ask about it later.

Walk Around the Outside

Stand at each corner and look down the side of the car. Waves in the reflection often mean body work. Then look closer.

• Gaps between panels should be even. A wide gap on one side can mean a panel was replaced or bent.
• Paint should match from panel to panel. A slightly different shade on one door is a clue.
• Look for paint overspray on rubber seals, trim and door jambs.
• Check the glass for chips and cracks, and look at the small print on each window. Mismatched glass can mean a window was replaced.
• Open and close every door, the hood and the trunk. They should close easily and line up.

None of these proves the car was wrecked. Plenty of cars get a door repainted after a parking lot scuff. But each clue is a question to ask, and a reason to read the history closely.

Read the Tires

Tires are cheap to check and expensive to replace. Put a penny in the tread with the head of Lincoln facing down. If you can see his whole head, the tread is worn out.

Look at the wear pattern too. Wear on only the inside or outside edge often points to an alignment problem or worn suspension parts. Cupped or patchy wear can mean worn shocks.

Every tire has a four digit date code on the sidewall. The first two digits are the week and the last two are the year it was made. Old tires can look fine and still be hard and unsafe. Our guide on tires as a safety check goes deeper.

Check Under the Hood

Only do this with the engine off and cool. You are looking for signs of neglect and leaks, not doing repairs.

• Pull the oil dipstick. Oil should look brown or amber. Milky or foamy oil can mean coolant is mixing with it, which is a serious problem.
• Look at the coolant tank. The level should sit between the marks and the fluid should look clean, not rusty or oily.
• Look at belts and hoses for cracks, fraying or soft spots.
• Check the battery posts for heavy crust and look for a date sticker on the battery.
• Look for fresh oil or wet spots around the engine. A very clean engine on an older car can mean someone washed away a leak.

Then look at the ground where the car was parked. Drips of oil, coolant or transmission fluid are worth asking about.

Look Inside the Cabin

The inside tells you how the car was used. Wear on the seat, pedals and steering wheel should match the miles. A worn out driver seat on a car with low miles does not add up.

Turn the key to on without starting the engine. Every warning light on the dash should light up for a moment. Then start the car. They should all go off. A light that never comes on at all may have been disabled.

Test everything that has a switch. That means windows, locks, mirrors, seats, the radio, the heat and the air conditioning. Smell the carpet and look under the floor mats for damp spots or stains. A musty smell is a warning sign of a leak or flood damage, which we cover in signs of flood damage.

What You Cannot See on Your Own

A careful walkaround weeds out a lot of bad cars. But the most expensive problems often do not show from a driveway.

A scan tool can show stored trouble codes and whether the readiness monitors are complete. If they are not, the codes may have been cleared right before the sale. Read how sellers hide a check engine light to see how that works.

Under the car, a mechanic can see rust, leaks, damaged frame rails and worn suspension parts. On a road test, a trained ear can tell a wheel bearing from a tire noise. Take your own drive too, using our guide on how to test drive a used car.

Buying from a dealer? Look up how past buyers rated the lot in our dealer directory before you go.

When to Bring In a Professional

If the car passes your own check and you still want it, that is the right time for an independent inspection. Our used car inspection covers 122 points, a full OBD-II scan with readiness monitors, a road test, tire and brake measurements, and photos of anything we find. We go to the car at the dealer, a private seller or an auction. You do not need to be there, and the report comes the same day.

Common Questions

Get the Car Inspected