The Bosch diesel fuel injector 0445110941 is a common rail fuel injector used in various diesel engines, particularly in European vehicles.

• Part Number: 0445110941 (Bosch OEM)

• Type: Common Rail Solenoid Injector

• Applications: Used in multiple diesel engines, including some from Volkswagen, Audi, Skoda, Seat, and others with 1.9 TDI, 2.0 TDI, and similar engines.

• Compatible Vehicles:

• VW Golf, Passat, Jetta (1.9 TDI / 2.0 TDI)

• Audi A3, A4, A6 (TDI models)

• Skoda Octavia, Superb

• Seat Leon, Alhambra

Symptoms of a Failing Injector:

• Hard starting or misfires

• Rough idle or excessive vibration

• Black smoke from exhaust

• Increased fuel consumption

• Error codes (e.g., P0201-P0204 for injector circuit issues)

  The Bosch diesel fuel injector (0445110941) is a solenoid-controlled common rail injector designed for precise high-pressure fuel delivery in modern diesel engines. Below is a breakdown of its structural characteristics:

• 1. Main Components of the Injector

• A. Nozzle Assembly (Tip Section)

• Nozzle Body & Needle Valve

• Made of high-strength steel to withstand extreme pressures (up to 1,800 bar or more).

• The needle valve opens/closes to control fuel spray.

• Spray Holes (Orifices)

• Typically has microscopic holes (5-8 holes, ~0.12mm diameter) for atomized fuel delivery.

• Designed for optimal spray pattern (cone-shaped for efficient combustion).

• B. Solenoid Actuator (Top Section)

• Electromagnetic Solenoid Coil

• Receives electrical signals from the ECU to open/close the injector.

• Operates at high speed (response time in milliseconds).

• Armature & Valve Ball

• Moves when energized, allowing high-pressure fuel to flow to the nozzle.

• C. Hydraulic Control System

• Control Piston & Pressure Chamber

• Uses fuel pressure to assist in needle lift (hydraulically amplified).

• Check Valve (Non-Return Valve)

• Prevents fuel backflow, maintaining pressure stability.

• D. High-Pressure Fuel Connections

• Common Rail Inlet

• Connects to the high-pressure fuel rail (via a banjo bolt or threaded fitting).

• Leak-Off Port (Return Line)

• Returns excess fuel to the tank via a leak-off pipe.

• 2. Key Structural Features

• A. Multi-Layered Sealing System

• Copper Washer (Sealing Cone)

• Ensures a high-pressure seal between the injector and cylinder head.

• O-Rings (Upper & Lower)

• Prevent fuel leaks at the injector-body interface.

• B. Precision Machined Internal Passages

• Fuel Ducts & Control Channels

• Direct fuel flow with minimal pressure loss.

• Pressure Relief Orifices

• Helps manage hydraulic forces for smooth needle movement.

• C. Robust Housing Material

• Hardened Steel Body

• Resists thermal expansion and mechanical stress.

• Heat-Resistant Coatings

• Protects against extreme temperatures in the combustion chamber.

3. Functional Design Highlights

• Fast Response Solenoid — Enables multiple injections per cycle (pilot, main, and post-injections).

• Balanced Needle Valve — Hydraulic forces assist in quick opening/closing.

• Integrated Filter — Some models include a micro-filter to prevent clogging.

4. Common Failure Points in Structure

• Nozzle Coking — Carbon buildup blocks spray holes.

• Solenoid Wear — Electrical failures or slow response.

• Leaking O-Rings/Seals — Causes fuel leaks or pressure loss.

• Needle Valve Sticking — Due to deposits or wear.