Guide · 5 min read
Inspecting a used car before you buy it
A used car can be made to look perfect for the length of one viewing. These are the checks that are hard to fake, in the order they catch the most.
The short version
What to take away
- A seller can clear fault codes. Ask to see the readiness monitors — if they are not set, the car was scanned recently.
- Compare paint thickness panel to panel. Do not memorise numbers; find the panel that disagrees with its neighbours.
- The four-digit code on each tyre is week and year. Four tyres from four different years tells a story.
- Get underneath. Sill welds and underbody repairs are where accident damage hides.
- A short inspection is a snapshot, not a warranty. Anyone who tells you otherwise is overselling it.
We service and repair cars in Bengaluru — at your home or office, or at our workshop when the job needs a lift. Open 24 hours, every day.
No price is listed anywhere on this site because it depends on your car and the parts chosen. You get an itemised quote before any work starts.
1. The check most buyers miss: cleared fault codes
Fault codes can be cleared in seconds. A car with a misfire, a failing sensor or an intermittent fault can be reset before you arrive, and it will drive perfectly for the first fifty kilometres or so — long enough to complete a viewing and a test drive.
The giveaway is not the codes. It is the readiness monitors — the internal self-tests a car's engine management runs as you drive. Clearing the codes resets them all to "not ready". A car that has genuinely been driven normally has them all set.
Ask this on the viewing. Ask to see the readiness monitors on a scan tool. If several are not ready, somebody cleared the codes recently — and the fair question is why. That is not proof of a fault, but it is a reason to look harder before you pay.
2. Paint: compare the panels to each other
A paint thickness gauge reads how much paint is on a panel. The absolute number matters less than the comparison — factory paint is applied consistently, so all the panels on an unrepainted car read in a similar range.
Walk the car and read every panel. If one reads much higher than its neighbours, that panel has been repainted. That is not automatically bad: bumpers get resprayed for parking scrapes all the time. But it is a question to ask, and if the answer is vague, look harder at that corner of the car.
3. Tyres tell you what has been replaced
Every tyre has a four-digit code on the sidewall: the week and the year it was made. Read all four.
- Four tyres of the same age, matching the car's mileage — consistent with a car that has been looked after.
- Four tyres from four different years — someone has been replacing them one at a time as each failed, which often means the car has been run on a tight budget.
- A much newer tyre on one corner can indicate that corner took an impact.
- Odd brands mixed across axles is worth noting, though it is more common than the other patterns.
4. Get underneath it
This is where accident repairs live, because almost nobody looks. A seller will happily let you walk around the car and will often be reluctant about a lift — which is itself information.
Look at the sill seams and the floor pan for fresh underseal, uneven seam sealer, or welding that does not match the factory. Look at the chassis legs and the suspension mounting points for creases or fresh paint. A car that has had structural repair is not automatically unsafe, but the price should reflect it and you should know before you buy.
5. Start it cold, and arrive early
Arrive before the seller has had a chance to warm the car up. A warm engine hides cold-start faults: rough running, blue smoke, a rattle on startup, and a slow first crank all disappear once the engine is at temperature.
Put your hand on the bonnet when you arrive. Warm means it has been running, and you should ask why.
What a short inspection cannot promise
Honesty matters more here than anywhere else on this site, because you are about to spend a large amount of money on the strength of someone's opinion.
- It cannot see inside the engine, the gearbox or the differential. No inspection short of dismantling can.
- It is a snapshot of one day. A component that fails next month may have been perfectly healthy on the day.
- It cannot tell you how the car was driven or serviced before you owned it.
- It is not a warranty, and it does not transfer any liability to the inspector.
What it does do is find the expensive things that are visible to someone who knows where to look, before the money changes hands. That is worth a great deal, and it is worth being clear that it is all it is.
Asked next
Questions this usually raises
- Can a seller really hide a fault by clearing the codes?
- They can clear the stored codes, yes, and the car will usually run normally for a while afterwards. But clearing the codes also resets the readiness monitors, and those take driving time to set again. So asking to see the monitors is a reliable way to tell whether the car was scanned recently.
- Is a repainted panel a reason to walk away?
- Not on its own. Bumpers and doors get resprayed for ordinary scrapes constantly. What matters is why it was painted and how well it was done — a panel that has been filled and repainted heavily, on a corner that also shows suspension or sill damage, is a different proposition from a bumper with stone chips.
- How long does an inspection take?
- A useful one takes about forty minutes to an hour. Most of that is the underbody and the scan, which is where the expensive findings usually are. Anyone offering a five-minute check is doing a walkaround, not an inspection.
If it comes to that
The services this usually involves
Only if the checks above point at something. Nothing here needs booking in advance of knowing that.
Pre-purchase Inspection
An independent check before you buy — engine, body, electricals and a written report.
Doorstep or workshop
Diagnostics
OBD scan, fault-code reading and a plain-English explanation of what the warning light means.
Doorstep or workshop
Brakes & Clutch
Pads, discs, drums, brake fluid and clutch assembly work — inspected before anything is replaced.
Doorstep or workshop
Also worth reading
More guides
Drove through flooded water? What to check on your car
What to check after driving through standing water — the brake noise that is normal, the wet carpet that quietly costs money, and the one thing never to do if the engine stalled.
5 min read
Doorstep car service: what can and cannot be done in your parking
Which car jobs genuinely need a workshop and why, and which are fine at your apartment parking. Two questions sort any job, whichever garage you use.
4 min read
Next step
If you would rather someone just looked at it
Send us the car’s make, model and year, your area, and what it is doing. We will tell you what it needs and whether it can be done at your place or at our workshop — before anything is booked.