Toyota 1CD-FTV

Toyota's first common-rail diesel — the 2.0 D-4D — in the Corolla, Avensis, RAV4 and Previa.

It is the engine that taught Toyota's European customers what a diesel particulate filter does, and its faults are almost all in the emissions and fuel equipment rather than the engine.

Carbon is the theme. The exhaust-gas recirculation valve and the intake manifold coke up heavily, and on a short-journey car the loss of power arrives gradually enough that the owner adapts to it. A tired-feeling 1CD-FTV with no fault code is very often an intake that has closed up, and cleaning it is the repair.

The injectors are the other half. Their seats and seals leak combustion gases, which produces the sooty crust that makes an injector hard to remove — and on this engine the fuel system is sensitive enough that a failing injector shows as rough running long before a code names it.

Cylinder head trouble is documented on early examples, severe enough that Toyota extended coverage in several markets. On any 1CD-FTV, the question is which revision it is and whether the head has been done, and a car with no history is worth a compression test rather than a hopeful purchase.