2AD-FTV 2.2 D-4D

Coolant disappearing with no visible leak, the temperature gauge moving under load, and in later stages white exhaust smoke and overheating. The cylinder head can distort where it meets the gasket, letting combustion pressure into the coolant. Toyota revised the head and extended warranty coverage in several markets, so which head is fitted matters more than the mileage.

Check: Check the coolant level and look for oil or residue in the expansion tank, ask directly for head or warranty paperwork, and treat unexplained top-ups as the fault until proven otherwise.

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.