Buy & sell
Red flags before you fall in love
Two checklists — Domestic US volume vehicles and European luxury — so the Cars floor covers both markets, not just Euro complexity.
Domestic US & trucks
Flood / water lines
criticalCheck carpets, spare well, seat tracks, and under dash for silt. Trucks used in storms are high risk.
Transmission slip or delayed engagement
criticalTest cold and hot. Rebuilds on late-model automatics are four-figure events.
Frame / brake line rust (salt belt)
criticalLift inspection for frame scale, fuel/brake lines, and bed mounts on older trucks.
Security light / multiple keys missing
highMissing keys on PATS/Passlock-class vehicles can mean expensive programming or prior theft recovery issues.
Hacky remote start / stereo / trailer wiring
highLook under dash and at battery for poor grounds and tapped circuits — #1 parasitic source.
4×4 bind, clunk, or inoperative
highCycle 2H/4H/4L on safe surface. Encoder motor and transfer case repairs add up.
Oil consumption / tick on known engines
watchResearch engine family TSBs. Ask for oil-change interval proof.
Airbag or ABS light on
highBudget scan + clock-spring / sensor work. Do not assume “just a sensor.”
Thin service history on high-mile trucks
watchTiming chains, spark plugs on DI engines, and transmission service intervals matter.
European luxury
No coding / programming notes after modules
highBattery, modules, or keys without shop documentation is a red flag for future no-starts.
Cowl / sunroof drain water ingress
criticalCorroded connectors under carpets and in module cavities are classic Euro gremlins.
Wrong battery type or no registration
highAGM skipped or flooded installed where AGM required — chronic charging faults.
Recent glass without calibration proof
highLane keep / ACC warnings after windshield work need paid calibration.
Only one key on complex immobilizer
watchSpare key programming can be dealer-only and expensive.
No nearby independent with OEM-class tools
watchOwnership cost explodes if every job is dealer-only.
PPI tip
A pre-purchase inspection with a shop that owns a capable scan tool beats a free “code pull” at a parts store. Budget the inspection — it is cheaper than a surprise transmission or coding nightmare.

