Direct Answer: To accurately diagnose Mercedes OM651 engine misfires linked to the Bosch 0445110574 injector, technicians must perform a dynamic return flow test to identify control valve wear. Replacing worn units with OE-calibrated injectors and programming the IMA code into the CDI control unit restores rail pressure for W447 V-Class and Vito platforms.
Mercedes W447 / OM651 Injector Failure Symptoms
The Bosch 0445110574 common rail injector is the primary fuel delivery component for Mercedes-Benz V-Class (V200, V220, V250) and Vito commercial vans (W447 chassis, 2014 onwards) powered by the OM651 DE22LA BlueTEC engine. When these luxury transport or delivery fleets experience limp mode, DPF (Diesel Particulate Filter) rapid clogging, or extended cranking times, excessive back-leakage from worn injectors is the primary suspect.
Critical OM651 CDI Fault Codes Table
| OBD-II Code | Diagnostic Meaning | Root Cause in Mercedes OM651 Engines |
|---|---|---|
| P0087 | Fuel Rail Pressure Too Low | Triggered by massive return flow from worn 0445110574 control valves, preventing the Bosch CP4 pump from building adequate pressure. |
| P0201 – P0204 | Injector Circuit Open / Malfunction | Internal solenoid coil degradation. |
4-Step Diagnostic & CDI IMA Coding Protocol
Before authorizing expensive fuel system replacements on W447 platforms, technicians must execute these standard diagnostic steps:
- Run a Dynamic Return Flow (Leak-Off) Test: Attach graduated vials to the injector return ports. Crank the OM651 engine. Excessive leak-off volume immediately confirms internal valve seat wear inside the Bosch injector, directly causing the hard start or limp mode condition.
- Inspect the Copper Seals: The OM651 is notorious for “black death” (carbon blow-by). If you hear a chuffing sound, the copper sealing washers at the base of the injector have failed, which can mimic a misfire.
- Measure Static Coil Resistance: Disconnect the injector harness. Use a multimeter across the pins. Infinite resistance confirms a dead solenoid coil.
- Mandatory IMA Coding via XENTRY: When installing replacement 0445110574 units, the unique alphanumeric IMA code printed on the top of the injector MUST be programmed into the Mercedes CDI control unit. Skipping this causes rough idling, DPF clogging, and emission failures.
OE Cross-Reference Guide
Gottoparts supplies remanufactured Bosch units calibrated to exact factory tolerances for commercial and VIP transport fleets.
| Make & Model / Engine | Gottoparts Bosch Match | Mercedes OE Cross-Reference |
|---|---|---|
| Mercedes V 200, V 220, V 250, Vito (2014-) Engine: OM651 DE22LA (W447) |
0445110574 / 0445110573 | 651 070 31 87, A 651 070 31 87 6510703187, A6510703187 |
What is the Mercedes original equipment (OE) part number for the Bosch 0445110574 injector?
The Bosch 0445110574 and 0445110573 common rail injectors correspond directly to the Mercedes-Benz original equipment (OE) part numbers 651 070 31 87, A 651 070 31 87, 6510703187, and A6510703187, commonly fitted to the OM651 engine in W447 V-Class and Vito models.