Pre-purchase inspection

Audi A4 B8

Customized for a buyer who is not a mechanic. Focuses on what actually matters: the things that will hurt you financially if you miss them. Short, focused, with how-to detail.

Inspection version
18 items total. 10 marked high-priority. Print this page to save as PDF or hand to your mechanic.
Powertrain configuration
Engine
Gasoline
Induction
Turbocharged
Timing drive
Chain
Transmission
Automatic
Drivetrain
AWD

Before you go

  • Run the VIN through a history report

    High priority

    Pull both a Carfax AND an AutoCheck report. They source from different databases, and a clean report on one does not guarantee a clean report on the other. Look for accidents, title brands (salvage, rebuilt, lemon law), odometer rollback flags, and gaps in service history. If the seller refuses to share the VIN, walk away.

  • Check open recalls by VIN

    Enter the VIN at nhtsa.gov/recalls. Recalls are repaired at no cost to you at any dealership of the same brand, but unfinished recalls signal a previous owner who skipped maintenance. Major safety recalls (airbag inflators, brake systems) should be completed before purchase.

Paperwork

  • Title is clean and in seller name

    High priority

    The title must be a clean title, in the name of the person selling the car, with no liens listed. Salvage, rebuilt, junk, and lemon-law titles cut resale value in half and signal the car has been through something serious. A title in someone else name (parent, ex-spouse, business) means the seller cannot legally transfer it to you today.

  • Service records cover the last 5 years

    Ask for receipts, dealer service printouts, or a maintenance log. A complete record proves the previous owner actually changed the oil and addressed problems. No records does not always mean no service, but it does mean you cannot verify what was done.

Body and tires

  • Frame and undercarriage rust

    High priority

    Get a flashlight and look under the car. The frame rails (the long bars running front-to-back) should look mostly solid metal, not flaky orange scale. Surface rust is normal on any used car. Flaky, layered, or scaling rust on the actual frame is a deal-breaker because frame repair costs more than the car. Pay special attention to the leaf-spring mounts on trucks and SUVs, and the rocker panels under the doors on cars.

  • Panel gaps are consistent

    Walk around the car and look at the gaps between the hood and fender, the doors and body, and the trunk lid and quarter panels. They should be even on both sides. Inconsistent gaps mean the car has had bodywork, which often means an accident the Carfax did not catch.

  • Tire tread depth and age

    Use a penny: insert it into the tread with Lincoln head down. If you can see the top of his head, the tread is below 2/32 and the tire is illegal in most states. Then find the DOT date code on the sidewall (four digits like "3722" meaning the 37th week of 2022). Tires older than 6 years are aged regardless of tread depth and should be replaced for safety. A new set is $800 to $1,400 installed.

Engine

  • Oil condition and level

    High priority

    Pop the hood, find the oil dipstick (yellow handle on most cars), pull it out, wipe it clean, push it back in, and pull it out again. The oil should be honey-brown to dark amber, NOT black, NOT milky, NOT with metal flakes. Milky oil means coolant in the oil (head gasket). Metal flakes mean the engine is grinding itself apart. Oil below the minimum line on the dipstick on a car the seller knew you were coming to see is a major red flag.

  • Coolant condition

    High priority

    Find the coolant reservoir (a translucent plastic tank with "MAX" and "MIN" lines, usually labeled COOLANT). With the engine COLD (never open a hot system), the coolant should be a clean color matching the manufacturer spec: green, orange/pink, or blue. Brown, rusty, or oily-looking coolant is a sign of internal engine damage. If you see oil floating on top of the coolant, walk away.

  • Visible oil leaks

    High priority

    Look at the ground under where the car was parked when you arrived. Dry pavement is good. Drips, puddles, or dark stains indicate active leaks. Then look at the engine itself: wet, oily residue around the valve cover, oil pan, or anywhere on the engine block points to a leak. Small seeps are normal on older cars. Active drips on the ground mean repair bills in the near future.

Transmission

  • Transmission fluid condition

    High priority

    For automatic and CVT vehicles, the transmission fluid tells you almost everything. Some transmissions have a dipstick you can pull (similar to the oil dipstick). Healthy fluid is bright red or pink. Brown, dark, or burnt-smelling fluid is the smell of metal-on-metal wear and an expensive failure approaching. If the transmission is "sealed" and has no dipstick, ask for a service receipt instead.

Test drive

  • Cold start test

    High priority

    Insist on seeing the car started cold. If the seller offers to have the engine already warm when you arrive, that is a red flag worth pushing back on. A cold engine reveals problems a warm engine hides: timing chain rattle, lifter tick, blue smoke from worn valve guides, white smoke from a leaking head gasket. Listen for the first 30 seconds especially.

  • Watch for blue smoke under acceleration (turbo)

    High priority

    This engine has a turbocharger. Have someone follow behind in another car while you accelerate hard onto a highway on-ramp. Blue smoke from the exhaust under hard throttle means the turbo seals are failing and the engine is burning oil. A new or rebuilt turbo runs $1,500 to $3,500 installed. Walk away unless the seller is offering a major discount.

  • Highway acceleration is smooth

    Get on a highway and accelerate from 50 to 70 mph in one continuous push. The car should pull smoothly with no jerks, no hesitation, and no shudder. Listen for any whining noise that changes pitch with speed, which often signals differential or wheel bearing issues.

  • Hard braking test

    On an empty road, brake firmly from 40 mph to a complete stop. The car should stop straight without pulling left or right. The brake pedal should feel firm. Vibration through the steering wheel under braking means warped rotors. Pulling to one side means a stuck caliper or a brake imbalance.

Electronics

  • Air conditioning blows cold, heat blows hot

    Turn the AC to maximum cold with the fan on high. Cold air should come out of the vents within 30 seconds. Then switch to maximum heat. Hot air should come out within 60 seconds. A weak AC compressor is $800 to $1,500 to fix. A failed heater core can be $1,500 to $2,500 because the dash usually has to come out.

  • Every electronic feature works

    Test everything: all windows up and down, all door locks, all interior and exterior lights, turn signals, hazard flashers, sunroof if equipped, infotainment system, every steering wheel button, all dash warning lights cycle on with the key and then turn off, cruise control on the test drive. Electrical gremlins on older cars are time-consuming and expensive to diagnose.

  • OBD2 scan for pending codes and readiness

    High priority

    A $25 OBD2 reader (or a free Bluetooth one paired with a phone app like Torque) plugs into the port under the dash. Even if the check engine light is OFF, look for PENDING codes (problems the car has detected but has not fully confirmed) and READINESS MONITORS that have not completed. A car with all monitors marked "not ready" was likely scan-cleared in the last few days to hide a problem before the sale.

This checklist is a supplement to a professional pre-purchase inspection, not a replacement for one. A qualified mechanic with the right tools catches things a checklist cannot. Budget $150-300 for a proper PPI from a shop that knows this vehicle.