Buy wp20597 - Genuine Cummins Fuel Injector Kit – ISB/QSB 5.9L - 1 - wisentpartscenter.com

Description

The Genuine Cummins 0-986-435-503 Fuel Injector Kit includes six common rail diesel fuel injectors for compatible 5.9L Cummins ISB engines. These Bosch-manufactured injectors deliver precisely metered, high-pressure fuel into the combustion chambers, supporting proper fuel atomization, combustion efficiency, and engine performance. The injector family is commonly used in 2003–early 2004 Dodge Ram 2500 and 3500 trucks equipped with the 5.9L Cummins common rail diesel engine.

Key Functions

- Deliver precisely controlled quantities of high-pressure diesel fuel into each cylinder.
- Atomize fuel through precision injector nozzles for efficient combustion.
- Control injection timing and duration in response to engine management commands.
- Support consistent engine operation, throttle response, and power delivery.
- Help maintain proper combustion and emissions performance across different operating loads.

Fitment & Specifications

- Engine: Cummins ISB 5.9L common rail diesel
- Engine Displacement: 5.9L (5,883 cc)
- Vehicle Applications: Dodge Ram 2500 and 3500
- Model Years: 2003–early 2004, subject to engine identification
- Engine CPL References: 8213, 8228 and 8412
- Fuel System: Bosch high-pressure common rail
- Injector Type: Electronically controlled solenoid fuel injector
- Quantity: 6 fuel injectors
- Fuel Type: Diesel
- Manufacturer: Bosch, for the corresponding Cummins injector family

Verify fitment with us before ordering to ensure the correct part for your application.

Purpose of the Part

The Cummins 0-986-435-503 fuel injectors supply precisely timed and metered diesel fuel to the engine's six cylinders. Each injector receives high-pressure fuel from the common rail and opens electronically under commands from the engine control module, delivering fuel through a precision nozzle directly into the combustion chamber.

Proper injector operation helps maintain smooth combustion, consistent power delivery, fuel efficiency, and reliable engine starting. A matched set of six injectors allows replacement of the complete injector group when testing or engine repair requirements indicate that all six should be replaced.

Issue Symptoms / When to Replace

Worn, leaking, or malfunctioning fuel injectors can affect fuel delivery and combustion quality. Common signs that the injectors may require inspection or replacement include:
- Difficult starting or extended cranking.

- Rough idle, engine misfires, or uneven cylinder operation.
- Excessive white or black exhaust smoke.
- Reduced engine power and poor acceleration.
- Increased fuel consumption.
- Excessive injector return flow or difficulty maintaining fuel rail pressure.
- Diesel knock or abnormal combustion noise.

Similar symptoms can result from low fuel supply pressure, a failing high-pressure pump, leaking injector connector tubes, fuel contamination, or electrical problems. Injector return-flow testing, cylinder diagnostics, and fuel-system inspection should be performed before replacement.

Brand Information

Cummins is a major manufacturer of diesel engines and power systems, including the ISB and QSB engine families used in commercial vehicles and industrial equipment. Bosch is a leading manufacturer of diesel injection technology and supplied common rail fuel injectors for Cummins 5.9L engine applications. Bosch injector manufacturing and calibration are important to maintaining the intended fuel delivery characteristics of these engines.

Installation Notes

Keep the fuel system clean during installation and inspect the injector connector tubes, sealing surfaces, and high-pressure fuel connections. Replace injector sealing washers and connector-tube seals as required by the Cummins service procedure, and verify the correct injector orientation and seating.

Follow the specified tightening sequence and torque procedures for the injector hold-downs and fuel connections. Prime the fuel system as required, inspect for leaks, and verify proper engine operation after installation.

How to Identify an OEM Part

Genuine Bosch-manufactured Cummins injectors can be identified by their Bosch identification markings and production codes on the injector body. The corresponding injector family includes Bosch numbers 0445120018, 0445120113, 0445120210 and 0445120255. Compare these markings with the original injector and confirm the correct Cummins application before installation.

Why Buy 0-986-435-503 From Wisent Parts Center?

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Warranty & Return Information
Warranty Information

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Wisent Parts accepts returns within 30 days of delivery. All returns are subject to a restocking fee. To qualify, parts must be unused and in their original condition. For full return instructions and restocking fee details, please refer to the Returns page.