Rust & corrosion

Rust and corrosion on a used car · where to look

Rust is the one fault that gets worse while the car sits still. Cosmetic bubbling is a haggling point; structural corrosion is a walk-away.

Quick answer

Rust & corrosion appears as a documented fault on 196 models in our library, across 255 separate faults. The most common areas involved are Bodywork, Brakes, Body, Cooling System, Engine Cooling, Engine.

What it usually means

  • Bubbling along arch lips and door bottoms · cosmetic now, structural later.
  • Flaking on sills, jacking points or the boot floor · likely a test advisory or failure.
  • Corroded brake lines and subframes · safety-critical and expensive to do properly.
  • Fresh underseal on an older car can be maintenance or a cover-up.

How to check it on the forecourt

  1. 01Run a hand along the inside of each arch and along both sills.
  2. 02Lift the boot carpet and the spare wheel well and look for damp and scale.
  3. 03Torch the subframe mounts, brake lines and fuel lines.
  4. 04Check the last few test histories for corrosion advisories.

Models where this is documented

Each entry links to that model's full fault page, with onset mileage, severity and what to inspect.

Toyota Aygo2014–20244 matching faults
  • Rear arch corrosion and stone chips· 8+ years
  • Water ingress into the boot and rear cabin· 40,000-60,000 miles or 5+ years
  • Water pump bearing failure and coolant leaks· 40,000-70,000 miles
Mazda CX-32015–20223 matching faults
  • Corrosion around the arches on older cars· Age-related
  • A/C blows warm air due to condenser failure from stone damage or internal corrosion.· 40,000-70,000 miles
  • MZD Connect infotainment screen suffers from 'ghost touch' or visible delamination under the glass.· 30,000-60,000 miles
Mazda Mazda22015–20253 matching faults
  • Rear arch and sill corrosion on older cars· 7+ years
  • Rear disc corrosion on low-mileage cars· Age-related
  • Air conditioning blows warm due to a punctured or corroded condenser, which is heavily exposed to stone chips behind the wide front grille.· 40,000-80,000 miles
Nissan Leaf2013–20243 matching faults
  • Rear disc corrosion from regenerative braking· Age-related
  • Creaking or clunking noise when turning the steering wheel at low speeds due to rusted top strut mount bearings.· 40,000-70,000 miles
  • Damp boot carpet, excessive cabin condensation, or a musty smell caused by failing rear bumper pressure relief vents.· 4-7 years
Peugeot Boxer2014–20253 matching faults
  • Corrosion on the chassis and rear crossmember· Age-related
  • Sliding door and door bottom corrosion· Age-related
  • Alternator failure or seized glow plugs caused by rainwater leaking through the windscreen scuttle panel joint directly onto the engine block.· 3-5 years
Skoda Citigo2012–20193 matching faults
  • Stone chip corrosion on front bumper edges and sills· Age-related
  • Water pooling in the spare wheel well or damp rear footwells due to failed rear pressure relief valve seals.· 4+ years
  • Air conditioning fails to blow cold air due to a holed or corroded AC condenser.· 50,000-80,000 miles
Toyota Yaris2012–20253 matching faults
  • Rear brake corrosion because regen does most of the braking· Age-related
  • Water ingress into the boot causing damp carpets, musty odours, and heavy cabin condensation.· 5+ years / 50,000+ miles
  • Water pump bearing wear leading to coolant leaks and potential engine overheating.· 60,000-80,000 miles
Alfa Romeo Giulietta2010–20202 matching faults
  • Dashboard warning lights and instrument cluster faults from wiring corrosion· Age-related
  • Paint bubbling around wheel arches and sills· Age-related
BMW 2 Series2014–20252 matching faults
  • Unexplained coolant loss and white residue around the expansion tank due to split seams or faulty caps on B48 and B58 engines.· 40,000-60,000 miles
  • A distinct metallic clunk or knocking noise from the front end when turning the wheel at low speeds, caused by a worn steering rack thrust piece.· 50,000-70,000 miles
BMW i42021–20252 matching faults
  • Corroded discs from regen braking use· 20,000+ miles
  • High-voltage system coolant leaks at the heat exchanger or Combined Charging Unit (CCU).· 15,000-40,000 miles
Citroen C12014–20222 matching faults
  • Water ingress into the boot area· 4-6 years
  • Rear silencer corrosion and blowing· 50,000-70,000 miles
Citroen Relay2006–20242 matching faults
  • Rust on chassis rails and rear door bottoms· Age-related
  • Water ingress from the scuttle panel causing rusted injectors and ECU faults.· From 3 years or 30,000 miles
Fiat 500X2015–20242 matching faults
  • Paint quality issues and stone chip corrosion on lower panels· Age-related
  • Coolant leaks leading to potential overheating, commonly originating from a cracked plastic thermostat housing or degraded seal.· 40,000-60,000 miles
Fiat Ducato2014–20252 matching faults
  • Corrosion on the chassis and rear crossmember· Age-related
  • Alternator failure and electrical shorts caused by rainwater bypassing the windscreen scuttle panel and pouring onto the engine.· 3-5 years or 40,000+ miles
Fiat Panda2012–20252 matching faults
  • Corrosion on the arches, sills and tailgate· Age-related
  • Oil leak or weeping from the bottom of the engine block caused by a heavily rusted mild steel oil sump pan.· 6-8 years or 50,000+ miles
Fiat Punto2005–20182 matching faults
  • Rust on sills, rear arches and around the tailgate· Age-related
  • Oil weeping or dripping from the bottom of the engine due to a heavily corroded mild steel sump pan on 1.2 and 1.4 FIRE engines.· 8-12 years
Ford Explorer2016–20192 matching faults
  • Bubbling or blistering paintwork on the front leading edge of the bonnet.· 3-5 years or 40,000+ miles
  • Rear-end sway at speed, clunking over bumps, or severe inner tyre wear.· 60,000-90,000 miles
Ford F-1502015–20202 matching faults
  • Aluminum panel corrosion / dissimilar-metal reactions at fasteners.· Age-related
  • Door latches freezing or failing to catch, preventing doors from closing securely.· 3-5 years
Ford Fiesta2013–20232 matching faults
  • Damp boot carpet, heavy cabin condensation, and a musty smell caused by failing rear pressure relief vent seals or cracked roof seam sealer.· 5+ years or 50,000 miles
  • Engine misfire, hesitation under load, or an illuminated EML caused by water leaking through the bonnet washer jets into the spark plug wells.· 40,000-70,000 miles
Ford Ka2016–20202 matching faults
  • Rear arch and tailgate corrosion· Age-related
  • Coolant leaks from the plastic thermostat housing degrading over time.· 50,000-80,000 miles
Ford Mustang2015–20232 matching faults
  • Paint blistering and bubbling on the leading edge of the aluminium bonnet due to galvanic corrosion and poor factory preparation.· 3-5 years
  • SYNC 3 infotainment screen becomes unresponsive, freezes, reboots randomly, or shows physical delamination (air bubbles) under the glass.· 40,000-80,000 miles
Ford Puma2019–20252 matching faults
  • Rear brake corrosion from low usage on hybrid cars· Age-related
  • Coolant leaks from expansion tank seams or return pipes· 40,000-70,000 miles
GMC Sierra 15002014–20182 matching faults
  • IntelliLink touchscreen delamination causing dead spots or erratic 'ghost' touches that change settings randomly.· 4-6 years
  • Factory wax-based frame coating peeling off in large flakes, exposing the bare steel chassis to rapid surface corrosion.· 3-5 years
Honda Jazz2015–20252 matching faults
  • Rear brake corrosion on low-mileage cars· Age-related
  • Water ingress into the boot area caused by cracked roof seam sealant near the tailgate hinges or failing rear light cluster seals.· 5+ years
Hyundai i102013–20252 matching faults
  • Rear beam and shock wear from potholes· 70,000+ miles
  • Door edge and tailgate corrosion on older cars· 8+ years
Kia Niro2016–20252 matching faults
  • Rear disc corrosion from regenerative braking· Age-related
  • Coolant loss and sweet smell from the exhaust heat recovery system (EHRS) or EGR cooler on 1.6 GDi models.· 50,000-80,000 miles
Kia Picanto2013–20252 matching faults
  • Rear drum and disc corrosion on low-mileage cars· Age-related
  • Coolant weeping from the water pump gasket or weep hole, which can lead to overheating if left unchecked.· 60,000-90,000 miles
Kia Stonic2017–20252 matching faults
  • Stone chip corrosion on lower door edges and sills· Age-related
  • Premature rear brake disc scoring and binding caused by seized rear caliper slider pins.· 30,000-50,000 miles
Land Rover Range Rover Sport2005–20222 matching faults
  • Hydraulic fluid leaking from corroded pipes, causing a red suspension warning and heavy knocking during cornering.· 70,000-100,000 miles
  • Rapid coolant loss and overheating on 5.0 V8 models due to the plastic crossover pipes splitting or water pump failure.· 50,000-80,000 miles
Lexus IS2013–20222 matching faults
  • Rear disc corrosion from regen use· 30,000+ miles
  • Electric water pump failure or leakage on the 2.5L hybrid engine.· 80,000-120,000 miles
Lexus NX2014–20212 matching faults
  • Disc corrosion from regen braking· 30,000+ miles
  • Water ingress pooling in the spare wheel well caused by failing rear light cluster seals or tailgate hinges.· 6-8 years
Mercedes-Benz B-Class2019–20252 matching faults
  • Rear disc corrosion on low mileage cars· Age-related
  • Coolant loss and sweet smell under the bonnet· 40,000-60,000 miles
Mercedes-Benz Sprinter2013–20252 matching faults
  • Rust on wheel arches, sills and door bottoms· Age-related
  • Coolant loss, sweet smell from the engine bay, or crust around the engine block.· 70,000-90,000 miles
Mitsubishi L2002006–20232 matching faults
  • Chassis and rear-body corrosion on older working trucks· Age-related
  • Corroded rear light and trailer wiring connectors· Age-related
Mitsubishi Shogun2007–20192 matching faults
  • Underbody and chassis corrosion, especially on towing vehicles· Age-related
  • Engine hesitation or stalling caused by dirt and water entering the fuel tank through a heavily corroded metal fuel filler neck.· 8-12 years
Nissan Ariya2022–20262 matching faults
  • State of health lower than expected on early high-mileage cars· 40,000+ miles
  • Rear disc corrosion from light friction-brake use· 30,000+ miles
Nissan Frontier2005–20192 matching faults
  • Bed and frame corrosion in salt regions.· Age-related
  • Sudden coolant loss and overheating due to brittle plastic heater hose connectors snapping.· 70,000+ miles or 8+ years
Nissan NV2002009–20212 matching faults
  • Sliding door and sill corrosion· Age-related
  • Rear barn doors fail to open from the outside or refuse to latch shut properly due to dirt ingress and corrosion in the lower catch mechanism.· 5-8 years
Peugeot 1082014–20222 matching faults
  • Water pooling in the spare wheel well· 4-6 years
  • Blowing noise and heavy corrosion on the rear silencer· 40,000-60,000 miles
Peugeot Traveller2016–20242 matching faults
  • Underbody corrosion on vans used for airport or taxi work· Age-related
  • Air conditioning blows warm air due to condenser stone damage through the large front grille or corroded rear AC pipes.· 3-5 years

Showing the 40 models with the most documented matches · browse the full library.

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