Kia 2.5 CRDi 170

A known weakness of the Kia Sorento JC D4CB: the internal fuel tank coating delamInates, blocking fuel filters and lines. Engine dies while driving; Kia may cover consequential costs with a complete service history.

Symptoms: Engine cuts out suddenly under partial load or at idle, hard starting after refuelling, fuel pump noise

On the D4CB 2.5 CRDi the timing chain stretches prematurely with long or overdue oil changes. Noise at start-up is an early warning sign; if ignored it leads to chain stretch and ultimately engine failure.

Symptoms: Rattling or clattering on start-up that fades as the engine warms; in advanced stages engine failure

The timing chain of the older 2.5 CRDi stretches prematurely and can snap if replacement is delayed, which is equivalent to a write-off. Late oil changes and short trips accelerate wear considerably.

Symptoms: Rattling on cold start, rough running, in severe cases engine failure or serious malfunction.

Injector problems are a typical Kia Sorento issue: leaking injectors cause blow-by effects with oil carbonisation. On vehicles built before Feb. 2008 the injector clamp torque was also incorrect (recall).

Symptoms: Fuel smell or leakage around injectors, increased oil consumption, rough running, in severe cases engine damage.

If the oil strainer is blocked by blow-by or spent oil, the turbocharger loses oil pressure and sustains irreversible damage. Often a secondary failure after injector blow-by.

Symptoms: Whistling or metallic grinding from the turbo area, blue smoke, power loss, engine warning light.

The D4CB's EGR valve and injectors tend to carbon up with age, especially when driven frequently on short trips. Diesel additives can extend service intervals.

Symptoms: Engine warning light, misfiring, increased fuel consumption, poor acceleration when cold

Underbody rust is a widespread problem on the Sorento BL and significantly impacts MOT inspections. Inadequate factory corrosion protection on cross members and longitudinal frame rails.

The transfer case is very sensitive to different tyre diameters and unequal tyre pressures. Permanent four-wheel drive on tarmac leads to overheating and chain damage in the gearbox.

On the Sorento BL with the 2.5 CRDi, the steering rack develops significant stiffness after long motorway runs. Restarting the engine temporarily resolves the issue — a classic sign of a thermal steering rack problem.

On the Sorento BL, moisture can penetrate the climate control connector block in the left footwell. This causes short circuits and the simultaneous complete failure of the heater, blower and rear screen heater.