Range Rover L405 4.4 Fuel Injectors Insulation Lower Left N/S AH4Q-9U550-AA

The Range Rover L405 4.4 Injector Sound Deadening Cover Left AH4Q-9U550-AA is a specialized component in the injector nozzle category, designed for diesel engines. It ensures stable operating conditions for the left-side injectors, reducing noise and the impact of adverse external factors.

Specifications and technical data

• SKU: LR022923
• Mark: Range Rover
• Condition: Used
• OEM Part Number: LR022923
• Substitutable numbers: LR022923, AH4Q9U550AA, AH4Q-9U550-AA
• Location on the vehicle: Left
• Fuel type: Diesel
• Category: Fuel Injectors

Purpose and Function of the Injector Sound Deadening Cover

The left-side injector sound deadening cover is a structural element designed for the specific diesel engine in the Range Rover L405 4.4 model. Its purpose is to create a controlled operating zone for the injectors, which translates to:

• reduction of noise characteristic of diesel injection, particularly audible in the engine bay,
• protection of injectors from contamination and small particles that may enter the injector rail area,
• thermal stabilization of the injector area, promoting consistent performance of the fuel system.

This solution supports the refinement of the powertrain's operation and facilitates the maintenance of predictable injection parameters during daily use.

Construction and Fit for Range Rover

The cover has been developed with the specific engine bay layout of the Range Rover in mind, ensuring:

• precise fit to the left side of the injector housing, without the need for modifications or on-site adjustments,
• preservation of the original geometry for routing of lines and accessory components around the injectors,
• compatibility with Diesel fuel systems, accounting for characteristic thermal and acoustic loads.

This precise fit helps maintain the integrity of the entire injection system and simplifies vehicle servicing according to manufacturer specifications.

Benefits of Using the Injector Sound Deadening Cover

Using the correct left-side injector cover provides tangible operational benefits:

• a more comfortable acoustic environment in the cabin and outside the vehicle, especially at idle and low RPMs,
• enhanced protection for critical fuel system components against dust, moisture, and localized temperature fluctuations,
• maintenance of the original assembly standard, which is important for further diagnostics and potential fuel system repairs.

For Range Rover diesel engines, a correctly selected sound deadening cover is a crucial element contributing to the refinement of operation and the longevity of injector components.

Condition and Practical Application

The presented cover is part of the used genuine parts group, meaning it comes from a vehicle dismantling and retains a construction consistent with the manufacturer's original specifications. This type of component is particularly useful for:

• comprehensive servicing of the diesel engine's injection system,
• restoring the original engine bay configuration after previous repairs or missing parts,
• reducing additional vibrations and noise originating from the injector area.

Proper installation of the cover on the left side of the engine helps maintain the structural integrity of the entire system and facilitates subsequent servicing activities.

Technical Support and Additional Resources

If you are interested in other Range Rover injector nozzles and components from the same assembly group, check out the Range Rover injector nozzles available in our store to select a complete solution for your fuel system.

When working with diesel systems, it is beneficial to be aware of common signs of wear and malfunctions. Detailed information on symptoms and the consequences of neglect can be found in the article Diesel Injector Failures – How to Recognize Them and What Neglect Entails, which helps in better planning diagnostics and servicing.

If you want to maximize the potential of dismantled components, practical tips on operation and maintenance can be found in the entry How to Extend the Lifespan of Used Car Parts?, describing proven methods for caring for components used in engines, suspension, and electronics.