Hyundai D4CB (2.5 CRDi)

Hyundai's 2.5 common-rail diesel — in the H-1 and Starex vans and the first Sorento.

It is a commercial engine in commercial vehicles, and that shapes the fault list: these are worked hard, loaded, and very often run well past any interval anybody wrote down.

⚑ Cylinder-head cracking is the failure this engine is known for, and it presents as coolant loss with no external leak, then pressure in the header tank. On a van that has been overheated once, it is the first thing to test for — a chemical block tester answers it in ten minutes and before anything expensive is ordered.

The turbocharger is the second item, and its life tracks oil condition on an engine whose oil is very often overdue. A turbocharger that failed is usually reporting the oil, not a manufacturing fault.

Injectors and the fuel filter's water trap account for most running complaints, and in markets with poor fuel quality the filter interval matters more than the book allows for.

It is not the R-family 2.0/2.2 CRDi that came later and has its own page here — different architecture, different failures, and the CRDi badge on both is what causes the confusion.