2009 Ford C-MAX 2.0L Diesel · B9 NYT

The 1.6-litre 16V TDCi engine (DV6TED4) features an intricate turbocharger oil supply line containing a miniature wire mesh banjo filter. Over extended service intervals or when low-quality oil is used, soot and carbon from combustion blow-by accumulate in the shallow sump and block this micro-strainer. Starved of lubrication, the turbocharger bearings overheat, chatter, and seize, often shedding compressor wheel fragments into the intake tract or causing engine runaway if oil bypasses the turbine seals.

The front lower wishbones use large rubber void bushes at the rear pivot points to isolate road vibration from the cabin. On the heavy-bodied C-MAX, frequent cycling over UK speed cushions, potholes, and urban traffic calming causes the rubber bonding to delaminate, split, and tear. This allows excessive horizontal movement of the lower control arm, resulting in steering wander, accelerated inner tyre shoulder wear, and harsh knocking noises over road imperfections.