2AD-FHV 2.2 D-CAT

Coolant vanishing without a visible leak, temperature rising under load, and eventually overheating and white smoke. The same head distortion as the Toyota 2.2, on the higher-output version fitted to the IS. Lexus and Toyota extended warranty coverage in several markets, so documented head work is the thing that decides the car.

Check: Ask for head or warranty paperwork first, then check the coolant level and the expansion tank for residue. Unexplained top-ups should be treated as the fault.

Later parts: Revised cylinder head fitted under warranty programmes and in later production

Warning light, limp mode, oil level rising above the maximum mark from fuel dilution. The filter needs sustained hot running to regenerate. A car used for short urban trips never completes a regeneration cycle.

Check: Read the DPF soot load and the distance since the last regeneration on a scan tool, and check the engine oil level and smell it for diesel. Ask what the car was used for. A short-trip city diesel is the wrong car regardless of mileage.

Coolant loss with no visible external leak, white smoke, sweet smell. The EGR cooler cracks internally and leaks coolant into the intake. BMW recalled affected diesels over a fire risk from glycol deposits igniting.

Check: Check coolant level and look for unexplained top-ups in the service history. Verify the recall was carried out. It's free and searchable by VIN.