Used car inspection checklist

The twenty minute walkaround

Bring a flashlight, a magnet, a paper towel and a friend. The friend is for watching the exhaust while you start it, which is the one check you cannot do alone.

Insist on a cold start, and do not negotiate on it

This is the most important line on the whole list, and it is the one sellers most often quietly defeat.

A cold engine tells the truth. It reveals a rattle from a worn timing chain in the first two seconds. It shows blue smoke from valve stem seals. It exposes hard starting from weak compression or a failing fuel pump. It lets you hear a noisy lifter before the oil pressure comes up and quiets everything down.

A warm engine hides every one of those.

So when you arrange to see the car, say clearly that you want it cold and untouched when you arrive. If you turn up and the hood is warm, that is information in itself. It may be innocent. It may also be the third time this week somebody has failed to hear what the engine does on a cold start.

The honest move is to come back another day. If the seller will not accommodate that, you have learned something useful for free.

The bodywork checks that find crash repair

You are not looking for damage. You are looking for evidence of repair, which is a different and much easier thing to spot.

Panel gaps are the fastest tell. Walk around the car and look along the gaps at the doors, hood and trunk. Factory gaps are consistent, both sides, all the way along. A gap that is wide at one end and narrow at the other means a panel has been off and not perfectly refitted.

Paint texture next. Look along each panel at a shallow angle with the light behind you. Factory paint has a consistent slight texture. A resprayed panel often has heavier orange peel, or a very slightly different shade that only shows in daylight from an angle. Check the tops of the wheel arches and the edges of the door shuts for overspray on rubber seals.

Bolt heads tell you what has been unbolted. Open the hood and look at the bolts holding the fenders and hood in place. Factory bolts have undisturbed paint on the heads. Scratched or chipped paint means a wrench has been on them.

A cheap magnet finds body filler. It sticks to steel and slides off a thick patch of filler. Try it low on the doors and around the wheel arches, which is where both rust repair and collision filler live. Note that it tells you nothing on aluminium panels, which are increasingly common on newer cars.

And look at the seams inside the trunk and under the spare wheel. Factory seam sealer is neat and evenly applied. Hand-applied sealer over a repair looks exactly like what it is.

The four fluids that carry the most information

Bring a paper towel. This part takes three minutes and it can save you thousands.

Engine oil. Pull the dipstick. It should be brown to black and slippery. What you are looking for is a creamy, coffee-coloured emulsion, which means coolant has got into the oil. Also check the underside of the oil filler cap for the same mayonnaise texture. Note that a car doing only short trips can build a little condensation on the cap alone, so check the dipstick too before concluding anything. Coolant in the oil on both is a head gasket at best.

Coolant. Look in the reservoir when the engine is cold. It should be clean and brightly coloured. An oily film on the surface, rust, or brown sludge all point the same direction as the above.

Transmission fluid, on the cars that still have a dipstick for it. It should be red or pink and smell faintly of nothing much. Dark brown fluid that smells burnt means the transmission has been overheated, and that repair is often worth more than the car.

Brake fluid. Clean and light straw coloured is good. Very dark fluid means it has never been changed, which is both a cost and a decent proxy for how the rest of the car has been maintained.

Flood damage, which is worth its own section

Flooded cars get cleaned up and resold constantly, and a good detailer hides it well from a casual look. The damage is electrical, it appears months later, and it is effectively unfixable.

Lift the carpet in the footwells and the trunk, including under the spare wheel. You are looking for damp, silt, a tide line, or fine grit in places grit does not reach.

Smell it with the doors closed for a minute. Musty, or heavily perfumed with air freshener, both deserve attention. A strong deodoriser in a used car is covering something, even if it is only cigarettes.

Look at the metal that does not get cleaned. Seat rails, seat bolts, the springs under the seats, the bolt heads in the trunk, the metal brackets behind the dashboard. Surface rust on those in a car that is otherwise tidy is a serious signal.

Check for water lines or silt inside the headlight and taillight housings, and pull a seatbelt all the way out to look at the section that normally stays wound up inside the pillar, which is where staining survives a valet.

And test every electrical item, twice. Flood cars fail electrically in scattered, unrelated ways.

Nine things you cannot check in a parking lot

Everything above is worth doing and it will catch a good share of bad cars. Here is what it will not catch, honestly listed, because knowing the limits of a walkaround is part of using one well.

Stored and pending trouble codes, and whether the readiness monitors have been reset recently. A seller who clears codes the morning of the viewing shows you a clean dashboard. The readiness monitors reveal that the memory was wiped, and that is only visible on a scan tool.

Frame and unibody damage. Structural repair hides behind trim and underneath the car, and it is the difference between a repaired car and a written-off one.

Actual paint thickness. A gauge reads in microns and shows exactly which panels have been resprayed and how heavily. A magnet and a good eye get you part of the way.

Brake pad and rotor thickness. You cannot measure through a wheel. The pads visible through the spokes may look fine while the inner pads are gone.

Suspension and steering play. Ball joints, tie rod ends and bushings need the weight off the wheels and a pry bar to test properly.

Underbody rust and the state of the brake lines. On a car that has spent its winters on salted roads, this is often the item that decides whether it is worth buying at all.

Oil leaks, as opposed to oil residue. Telling an active leak from an old stain that was cleaned needs a proper look underneath with a light.

Cylinder compression and how evenly it is spread across the engine.

And the service history behind the odometer, including whether the mileage is consistent with recorded module data, which some makes store.

What we do, and what it costs

We meet the car wherever it is, at a dealer lot, outside a private seller's house, or in a parking garage, anywhere in Flushing and the rest of Queens, Brooklyn, Manhattan, the Bronx, Staten Island and Long Island.

We run a full mechanical inspection with the car up, factory-level scan tools on every module including stored codes, pending codes and readiness monitors, a paint gauge over every panel, brake and tire measurements, a suspension check, an underbody and rust inspection, and a road test.

You get a written report with photographs, a list of what the car needs, and rough costs for each item, usually the same day. That last part is what makes it useful, because it converts a vague sense that a car is a bit rough into a number you can either walk away from or negotiate with.

Inspections start at $95. Text us the listing link, the year and the make, and where the car is. We reply in under five minutes most of the time, and we can often get there the same day, which matters when a good car has three other people looking at it.

Common questions