For Volkswagen and Audi owners seeking a reliable, OE-grade replacement for the 3CD 919 051C fuel pump, the 56D919051 Fuel Pump Assembly offers a seamless upgrade with enhanced durability and diagnostic compatibility. This SEO-optimized guide combines technical specifications, cross-referenced applications, and performance insights to empower technicians and enthusiasts alike. 

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**1. Product Overview** 
The 56D919051 Fuel Pump Assembly is engineered as a direct replacement for the 3CD 919 051C, ensuring compatibility with Volkswagen Group’s turbocharged engines. Key features include: 
• Material: High-strength nylon housing with stainless steel internals, rated for -30°C to +120°C operation. 

• Design: 

  • Flow Rate: 120L/h at 3.5 bar (50 psi), optimized for direct-injection systems. 

  • Voltage: 12V DC with integrated pressure relief valve to prevent overpressurization. 

• Certifications: ISO 9001 and ISO/TS16949 compliant, ensuring OE-grade safety and performance. 


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**2. Technical Specifications** 
| Parameter          | Details                                | 
|-------------------------|--------------------------------------------| 
| Part Number         | 56D919051                                  | 
| OEM Cross-Reference | 3CD 919 051C, 3AA919051C, 5Q0919051BK | 
| Compatible Models   | VW Passat CC B6/B7 (2011–2016), Audi A3 Sportback (2012–2019) | 
| Pressure Range      | 2.5–5.0 bar (36–72 psi)                    | 
| Connector Type      | EV6-style 4-pin waterproof connector | 
| Warranty            | 24-month limited warranty         | 

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**3. Compatibility & Applications** 
• Engine Fitment: 

  • VW Passat CC 1.8 TSI/2.0 TSI: Turbocharged engines requiring precise fuel delivery under high load. 

  • Audi A3 2.0 TFSI: Direct-injection systems with dynamic fuel pressure demands. 

• Key Benefits: 

  • Eliminates fuel starvation during rapid acceleration. 

  • Reduces wear on high-pressure fuel injectors by maintaining stable pressure. 


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**4. Performance Advantages** 
1. Diagnostic Integration: 
   • Monitors real-time fuel pressure via CAN bus, triggering alerts (e.g., P0087/P0191 codes) for low pressure or pump failure. 

2. Corrosion Resistance: 
   • Zinc-nickel plating on internal components prevents degradation from ethanol-blended fuels (E10–E15). 

3. Energy Efficiency: 
   • 15% lower power consumption compared to older models (e.g., 3CD 919 051C). 


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**5. Installation Guidelines** 
Tools Required: Fuel line disconnect tool, torque wrench (8–12 Nm), OBD-II scanner. 

Steps: 
1. Depressurize the Fuel System: 
   • Disconnect the battery and relieve fuel pressure via the Schrader valve on the fuel rail. 

2. Replace the Assembly: 
   • Access the in-tank pump via the rear seat or trunk panel. 

   • Secure the 56D919051 assembly using OEM clamps (torque to 10 Nm). 

3. Post-Installation Checks: 
   • Prime the system by cycling the ignition 3–5 times. 

   • Use an OBD-II tool to validate fuel pressure (target: 4.0 bar). 


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**6. SEO-Optimized Keywords** 
• *OEM 56D919051 Fuel Pump Replacement for 3CD 919 051C* 

• *High-Pressure Fuel Pump Assembly for VW Passat CC 2.0 TSI* 

• *How to Diagnose P0087 Code in Audi A3 Sportback* 

• *ISO-Certified Fuel Pump for Ethanol Blends* 

• *Direct Injection Fuel System Upgrade Guide 2025* 


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Conclusion 
The 56D919051 Fuel Pump Assembly is a robust, diagnostic-ready solution for Volkswagen Group vehicles, combining advanced materials, energy efficiency, and seamless compatibility with the 3CD 919 051C legacy unit. Ideal for turbocharged engines and ethanol-blended fuels, it ensures reliable performance under extreme conditions. For bulk orders or technical support, consult authorized suppliers like eBay Motors or Amayama Trading, verifying fitment via VIN. 

References 
: Material certifications and pressure benchmarks. 
: Diagnostic code integration and installation protocols. 
: Cross-referenced OEM part numbers and compatibility data.