Ford Focus Turbo

Focus turbo: 5 petrol engine codes and 16 diesel engine codes, two very different forced-induction approaches

The Ford Focus turbo catalogue divides clearly between a diesel majority — 1.8 TDDi, 1.6 TDCi and 1.8 TDCi across several power outputs — and a petrol range comprising the 1.6 EcoBoost and the 2.0 EcoBoost ST and SCTi. These two worlds require very different types of turbo: on the diesel side, variable-geometry turbos with movable vanes (VGT) predominate, which means an actuator and a vane mechanism susceptible to soot fouling; on the petrol EcoBoost side, forced induction relies on fixed-geometry turbos with a wastegate, exposed to more severe thermal stresses due to petrol combustion temperatures and the high boost cycles of the ST and SCTi.

Diesel: three engine families, references that do not overlap

The 1.8 TDDi (codes C9DA, C9DB, C9DC) is the oldest of the Focus diesel engines; its turbo is distinct from those of the subsequent TDCi generations. The 1.8 TDCi comes in two sub-families: codes F9DA, F9DB, FFDA cover the 100 and 115 hp first generation, whilst KKDA and KKDB correspond to a later evolution of the 115 hp unit — these two groups do not share the same turbo references despite having the same engine capacity. The 1.6 TDCi is the most common and the most complex to identify: code HHDA appears on both the standalone 90 hp version and within the G8DA/G8DB/G8DD/G8DF/T1DA/T1DB family, which covers the 90, 109/110 and 115 hp outputs. Power output alone is not enough to determine the correct reference; the engine code stamped on the block is the only reliable starting point.

Petrol EcoBoost: wastegate and heat management, the key watch points

The 1.6 EcoBoost (JQDA, JQDB, JTDA, JTDB, YUDA) shares its platform across the 150 and 182 hp outputs, but turbo references may differ depending on the power level: checking the engine code remains essential. The 2.0 EcoBoost ST (R9DA) and the 2.0 EcoBoost SCTi each have their own turbo. On these petrol engines, failures frequently stem from lubrication breakdown at the bearings or from an oil seal leak on the turbo oil housing, both of which are aggravated by the high exhaust outlet temperatures. A persistent whistling noise or blue smoke on a cold start points towards the turbo, but fitting a new unit without having identified the root cause — oil circuit condition, air intake leak — will invariably lead to another failure. All turbos listed here are new parts, sold with no old unit to return.