Mercedes Sprinter High-Pressure Fuel Pump – Bosch | NCV3 3.0L OM642 Diesel | #6420701101 (2010–2018)

A failing high-pressure fuel pump on an OM642 Sprinter collapses the rail pressure the injection system requires to atomize fuel — causing rough idle, hard starts, power loss under load, and eventually a no-start that leaves the van stranded. This is the Bosch CP3 high-pressure fuel pump for NCV3 Sprinters equipped with the 3.0L OM642 V6 diesel engine, a direct replacement that restores correct common-rail fuel pressure and reliable injection system performance.

What This Part Does

The high-pressure fuel pump is a camshaft-driven plunger pump that takes low-pressure fuel from the lift pump and compresses it to the 1,600–2,000 bar required for the OM642's common-rail direct injection system. It feeds this pressurized fuel continuously into the fuel rail, which distributes it to six solenoid-controlled injectors. The pump's output pressure is regulated by a metering valve that the ECU controls — allowing the system to vary rail pressure based on engine load, RPM, and injection strategy. When the pump's internal plungers or check valves wear, or its metering valve develops a fault, rail pressure becomes unstable — causing the rough running, extended cranking, power loss, and fuel pressure fault codes that signal pump failure. Bosch is the OE supplier of this pump to Mercedes-Benz.

Common Symptoms of a Failing High-Pressure Fuel Pump

• Hard starting or extended cranking before the engine fires, particularly when cold
• Loss of power or sluggish acceleration under load — especially at highway speeds
• Rough idle that worsens as the pump's output drops further below specification
• Fuel pressure fault codes or rail pressure plausibility codes from the ECU
• Black smoke under acceleration from incomplete combustion caused by low rail pressure

When to Replace

Replace when rail pressure testing confirms the pump cannot reach or sustain specification under load. Always replace the fuel filter at the same time — contaminated fuel is a primary cause of pump failure, and a new pump on a dirty filter will fail prematurely. Flush the fuel system before installation to remove any debris from the failed pump. Note: the SKU suffix "B" indicates this is a remanufactured unit — a core charge may apply.

NCV3 OM642 Specific — VIN Verification Required

This pump is for NCV3 Sprinters equipped with the 3.0L OM642 V6 diesel engine. It is not compatible with VS30 Sprinters or NCV3 Sprinters equipped with the 2.1L OM651. Always verify your engine code and VIN before ordering. Contact us and we'll confirm fitment before you buy.

Fitment

• 2010–2018 Mercedes-Benz Sprinter 2500 – 3.0L OM642 Diesel (NCV3/W906)
• 2010–2018 Mercedes-Benz Sprinter 3500 – 3.0L OM642 Diesel (NCV3/W906)
• 2018 Mercedes-Benz Sprinter 3500XD – 3.0L OM642 Diesel (NCV3/W906)
• 2010–2018 Freightliner Sprinter 2500 / 3500 – 3.0L OM642 Diesel (NCV3)

✔ Always replace fuel filter when replacing the high-pressure pump
✔ Remanufactured unit — core charge may apply

Part Numbers

• Mercedes OEM: 6420701101 / A6420701101 / 642-070-11-01
• Cross-reference: 6420700901 / 6420701301 / 0445010322
• Manufacturer: Bosch
• SKU: 6420701101B