Kia Optima (TF) D4FD Injectors

Kia Optima (TF) D4FD Overview

The Kia Optima (TF) with the D4FD 1.7L CRDi engine was produced between 2012 and 2015. This vehicle uses Bosch common rail diesel injectors (primary part number 0445110411) operating at fuel pressures up to 2000 bar. The D4FD engine in the Kia Optima (TF) produces and of torque. When replacing injectors on the Kia Optima (TF) D4FD, always use new copper sealing washers and torque to manufacturer specifications. Each injector should be coded to the ECU after fitting.

Compatible Injectors

Common Injector Problems in Kia Optima (TF)

• •
  Rough idle and engine vibration — Worn injector nozzles cause uneven fuel spray, leading to rough idle at low RPM. Most noticeable when the engine is cold.
• •
  Excessive exhaust smoke — Black or blue-grey smoke on acceleration indicates poor fuel atomisation. This is often caused by carbon buildup on the injector nozzle tip.
• •
  Poor fuel economy — A worn or leaking injector delivers incorrect fuel quantities, reducing efficiency by 10–20% in severe cases.
• •
  Engine misfire under load — Intermittent misfires during acceleration suggest one or more injectors are failing to deliver the correct fuel pressure.
• •
  Difficult cold starting — Degraded injector nozzles struggle to atomise fuel at lower cranking pressures, causing extended crank times in cold weather.

Other D4FD Vehicles

Related Pages

Bosch 1.7L CRDi — browse compatible engines, vehicles, and injectors