HITACHI
03C127026R
View Specs
SolenoidHitachi / Bosch FSI/TSI 150-bar High Pressure Direct InjectionEuro 45
HITACHI 03C127026R High Pressure Fuel Pump Volkswagen Golf 5 6 Tiguan Touran Scirocco Audi A1 A3 1.4 TSI EA111 HPP0005
OE REFERENCE
03C127026P, 03C127026M, 03C127026J, HPP0005, HM10018CONTROL VALVE
Integrated Fuel Metering Valve N290NOZZLE
-RAIL PRESSURE
150 barEMISSIONEuro 4 / Euro 5
WARRANTY12 Months
02
Vehicle & Engine Fitment
| Vehicle | Engine | Years |
|---|---|---|
| Volkswagen Golf Mk5 / Mk6 / Scirocco / Tiguan | Volkswagen 1.4L TSI DOHC 16V Twincharger / Turbo EA111 (CAXA / CAVE / CAVD / CTHD / BLG / BMY) | 2006-2015 |
| Audi A1 8X / A3 8P | Volkswagen 1.4L TSI DOHC 16V Twincharger / Turbo EA111 (CAXA / CAVE / CAVD / CTHD / BLG / BMY) | 2007-2014 |
03
Technical Specifications
| Specification | Value |
|---|---|
| Operating PressureCore Spec | |
| Pump Technology | Single Plunger Mechanical Camshaft-Driven HPFP |
| Flow Control | Integrated Solenoid Metering Valve (N290) |
| Mounting Flange Torque | 20 N·m |
| High Pressure Line Torque | 27 N·m |
| Drive Type | Intake Camshaft Driven with Roller Tappet |
| Fuel Type | Gasoline / Petrol Direct Injection (TSI / TFSI / Twincharger) |
| OE Cross References | 03C127026R, 03C127026P, 03C127026M, 03C127026J, HPP0005 |
| Failure Symptoms | EPC warning lamp on acceleration, P0087 low rail pressure, hard starting, limp mode above 3000 RPM |
| Diagnostic Test | VCDS measuring block Group 106 & 140 (Specified vs Actual Rail Pressure under boost) |
04
Installation Tips
- [
- "Disconnect battery; pull fuel pump fuse and crank engine for 5 seconds to depressurize fuel lines.",
- "Disconnect electrical connector to N290 metering valve and unfasten low-pressure feed hose clamp.",
- "Counter-hold pump discharge union and loosen high-pressure steel tube flare nut using a flare wrench.",
- "Loosen the two M6 mounting bolts evenly in alternating turns to release internal spring tension evenly.",
- "Withdraw HPFP and inspect roller tappet in the cylinder head bore for flat spots or surface galling.",
- "Fit a new sealing O-ring lubricated with clean engine oil; seat pump into mounting bore.",
- "Tighten mounting flange bolts progressively in alternating steps to 20 N·m.",
- "Hand-thread high-pressure line flare nut until seated, then torque to 27 N·m; reconnect N290 connector.",
- "Cycle ignition several times to bleed air; start engine and inspect all joints for leaks."
- ]
05
Diagnostic Trouble Codes & Fault Protocols
Common diagnostic trouble codes (DTCs) triggered when this common rail injector experiences wear, circuit faults, or calibration drift:
P0087Critical
Fuel Rail / System Pressure Too Low
Excessive internal backleak from worn control valve seats drops common rail pressure below target under engine load.
P0201 - P0208High
Injector Circuit Malfunction / Open Circuit
Solenoid coil resistance drift (0.2-0.5 Ω) or piezo stack degradation triggers driver stage shutdown on affected cylinders.
P0300 / P0301+High
Cylinder Misfire & Balancing Deviation
Carbon-clogged nozzle spray holes or missing IMA calibration causes uneven cylinder contribution. Recode ECM and verify washer seating.
P0088High
Fuel Rail / System Pressure Too High
Spill line backpressure or stuck metering valve prevents rail depressurization, creating overpressure risks under load.
WORKSHOP PROTOCOLS
Technical Diagnostic & Service Protocols
Authoritative field procedures, diagnostic testing thresholds, and service SOPs for this assembly.
COMMON RAIL WORKSHOP DIAGNOSTICS
Read Technical ProtocolCommon Rail High-Pressure Pump Diagnostics Guide
COMMON RAIL WORKSHOP DIAGNOSTICS
Read Technical ProtocolFuel Metering Valve (IMV/SCV) Diagnostics Guide
OBD-II DIAGNOSTIC PROTOCOL
Read Technical ProtocolP0087 Low Rail Pressure Diagnosis Guide
COMMON RAIL WORKSHOP DIAGNOSTICS
Read Technical Protocol