Bosch 0445110574 CRI 2.0 Injector: Hold-Phase Stability & Anti-After-Injection Control for Ford Duratorq and GM/Opel CDTi

Q1: Can I replace a single 0445110574 injector, or does the whole set need changing?
You can replace a single injector, provided the ECU's adaptation range can compensate for any flow difference. However, if the engine has high mileage (>100,000 km), the remaining injectors will have elevated return flow, and the new injector will deliver more fuel than the worn ones, causing a slight imbalance. Replacing the set is recommended for optimal performance.

Q2: How do I perform a leak-off test on the 0445110574 in a Ford Duratorq engine?
Disconnect the return hoses from the injectors and connect clear tubing to graduated cylinders. Run the engine at idle for 60 seconds. A healthy injector returns ≤20 ml/min. If any injector exceeds 35 ml/min, it should be replaced. A variation of more than 8 ml/min between the highest and lowest cylinders is the earliest warning of wear.

Q3: Why does my Opel 2.0 CDTi start normally when cold but emits white smoke when starting hot?
This is typically caused by a worn control valve – at high fuel temperatures, the fuel's viscosity decreases, increasing internal leakage and causing an inadequate injection pressure during cranking. The ECU may over-fuel to compensate, resulting in white smoke. Replacing the affected injector resolves the issue.

Q4: What is the correct fuel filtration requirement for the 0445110574?
Bosch specifies a 5 µm absolute filter (β₅ ≥ 200) for the 0445110574. The 20 µm sintered inlet filter is a secondary protection, not a primary filter. Using a coarser primary filter allows abrasive particles to score the plunger and control valve, reducing the injector's service life by up to 40%.

Q5: Can the 0445110574 be used in a 1.9L TDI engine?
No – the 1.9L TDI uses a different injector body with a different mounting flange and nozzle flow requirement. The 0445110574 is physically longer and has a different clamp design. Using it in a 1.9L engine is not possible without modifying the cylinder head, which is not recommended.

Q6: What is the typical cause of an intermittent misfire that disappears above 2,500 rpm?
This is a classic symptom of needle stiction – the DLC-coated needle sticks in the guide at low rail pressures (idle) but is forced open at higher pressures. If a leak-off test shows normal values (<25 ml/min) but the misfire persists, the nozzle is likely carbonised. A commercial PEA-based injector cleaner may restore function; if not, professional ultrasonic cleaning is required.