What Should a Used-Car Inspection Include?

Even if you don’t have much mechanical knowledge, there are some simple checks and tests you can perform on a used car that should indicate whether certain major things are wrong. Many could be enough to disqualify a car from consideration.

Related: What to Ask When Buying a Used Car: 8 Key Questions

One of the standby pieces of advice has always been to take a prospective used car to a trusted mechanic to have it checked out. While that’s ideal — particularly if they can put it up on a lift — it usually isn’t practical. For one thing, the seller shouldn’t be expected to take the risk of letting you drive off in their car.

Slightly more practical is hiring a mechanic to go to the car. But scheduling can be tough, and a good car might get sold in the meantime. If you want to try this route and don’t know of someone who provides this service in your area, you might do a search for “mobile used-car inspectors in [your city].” Yet even if you can manage either of these options, it’s probably worth saving their time and expense until you’ve done some initial checks yourself.

Things You Can Check Yourself

One thing you can check is the car’s background history, which can be done through CarFax.com. (Competitors such as Autocheck.com, VINcheckup.com, and Bumper.com might be cheaper, but CarFax is the best known.) After entering the car’s 17-character vehicle identification number, the website will provide you with a history of when and where the car has been sold and registered, plus odometer readings — check these against the current odometer reading — and, sometimes, accidents, repairs, maintenance history and recalls performed. But since these reports cost something, you might want to do your own basic checks first.

What to physically inspect on a used car can be broken down into static checks and dynamic checks. We’ll make special note of the bigger issues to look for because if the car fails any of these, it may not be worth considering. Bring a flashlight, a towel to lay on (a big piece of corrugated cardboard is even better), hand cleaner, paper towels and a small magnet.

First, ask to see the title. If it’s a salvage or rebuilt title, you should probably steer clear, as both indicate the car may have suffered heavy body damage. Also, check to make sure the VIN on the title matches the VIN on the car. If it doesn’t, the car could be stolen.

Next, look for rust and telltale damage repairs. (Major damage repairs might show up on a CarFax report.) Bad rust or holes on the frame or subframes could be a deal breaker, as this is structural and can’t be easily fixed. Look down each side of the car to check for waves in the bodywork, and look straight on at all sides to make sure the paint matches and the bumpers are level. Check for body filler on anything that looks suspicious by placing a magnet against it (body filler isn’t magnetic) and examine the windows for cracked glass. Anything bad here may warrant disqualification.

Under the Hood

Underneath the hood, you should inspect the car’s fluids. Pull the oil dipstick and “feel” the oil at the bottom for grit, which indicates excessive engine wear, then look for water or a gray foamy substance — also bad. Remove the oil-fill cap and look for gray foam. You should also check the coolant overflow tank to ensure the coolant is green or orange, not whitish or rusty. If there’s a transmission dipstick (some newer cars don’t have one), pull it and see if the fluid is pink or reddish and not brown or with a burnt smell. Any “fails” here indicate things that could well go wrong soon and are expensive to fix.

Fire It Up

Next, check that all the doors open and get inside. If the carpet is damp or there’s a scent of mold or mildew, the heater core may be leaking or the car may have been in a flood. The former is bad, but the latter is far worse — and would warrant a pass.

Without starting the engine, turn on the ignition to illuminate the red and yellow warning lights on the dash. Then start the engine and make sure they all go out. Any that don’t go out indicate problems — many of which can be expensive to fix — and thus warrant further scrutiny or even disqualification.

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If you’ve been driving awhile, there are certain things you can “feel” that are wrong when you drive the car in question: loose steering, spongy or pulsating brakes, bobbing over bumps, odd noises (try to leave the radio and fan off so you can hear better), the engine running badly or the transmission shifting erratically. Particularly with engine and transmission problems, you should not accept a seller’s explanation that it “just needs a tuneup” or some other simple fix; if that were the case, they should have had it fixed themselves, and serious problems can cause the same symptoms.

If the vehicle is front-, four- or all-wheel drive, make tight turns and listen for clicking noises, which indicate a bad constant-velocity joint, a moderately expensive repair. A moaning sound while rounding corners can mean a bad (and often costly) wheel bearing. Turn the steering wheel full lock to both sides and look at the inside of each wheel hub for the CV boot — typically a black rubber cone with “bellows” — to check it for rips.

While you’re stopped, try the heat, air conditioning (turn the fan on different speeds), lights, turn signals, wipers and radio. You should also make sure the power windows, power door locks, power mirrors and power seats all operate properly.

With the engine still running, look underneath the car to check for any fluids leaking. You might also be able to check the exhaust system for leaks or patches, as well as if the catalytic converter is still there. (They’re often stolen, then replaced with a straight pipe.) Then check the exhaust for smoke. Blue or black smoke — or white smoke that remains after the engine has warmed up — indicates an engine problem you probably don’t want to deal with.

Even better in this regard is if you can take someone with you to follow you during your test drive. They can check for exhaust smoke and whether the car is “dog walking” — driving slightly crooked down the road — which indicates major body damage.

Check the Maintenance History

While some maintenance history may show up in a CarFax report, a stack of receipts lets you check how often the oil has been changed and when expensive maintenance items were last performed. One example of the latter that applies to many new cars is replacing the engine’s timing belt, which should occur about every 100,000 miles (sometimes sooner) and can easily cost $1,000.

If the car proves to be solid after your inspection, taking it to your mechanic to check or replace fluids, hoses, belts, brakes and other normal maintenance items after purchasing it can be a good idea.

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