Mercedes ML W166 GL X166 Fuel Pump Tank Fuel Sender Unit Petrol A1664700390

Mercedes ML W166 GL X166 Fuel Pump Tank Fuel Sender Unit Petrol is an original fuel system component designed for in-tank installation. Thanks to its factory-spec Mercedes design, it ensures stable fuel pressure and precise fuel level readings, which translates into proper engine operation and reliable indications on the instrument cluster.

Specifications and technical data

• SKU: A1664700390
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A1664700390
• Substitutable numbers: A1664700390, A 166 470 03 90, A1665400517, A 166 540 05 17
• Fuel type: Petrol
• Category: Fuel Pumps & Sending Units

Purpose and function in the fuel system

The described unit belongs to the Fuel pumps and level sensors category and is mounted directly inside the fuel tank in Mercedes ML W166 and GL X166 models. It is responsible for drawing fuel from the tank, filtering it, and delivering it at the appropriate pressure to the rest of the fuel system, while the integrated float transmits information about the fuel level to the ECU and the instrument cluster.

This type of solution is crucial for the stable operation of a gasoline-powered engine – a correctly selected pump reduces the risk of power loss, starting problems, or rough engine idling when the fuel level is low.

OEM selection and compatibility

The component was designed by Mercedes as an original part, which facilitates selection by OEM number and interchangeable part numbers in professional catalogs. This allows workshops or users to precisely verify compatibility with a specific version of the ML W166 or GL X166, minimizing the risk of installing an incorrect module.

The pump is designed for petrol fuel systems, therefore it should only be used in vehicles with gasoline engines, in accordance with the manufacturer's factory specifications.

Condition, advantages of the original component, and service application

The product is offered as a used part, which allows for an economical repair of the fuel system while maintaining the original Mercedes design. In practice, this means:

• maintaining the factory geometry and operating parameters of the pump,
• secure fitment to the basket and mounts in the fuel tank,
• compatibility with the electrical installation and engine control unit.

Such a solution is often chosen by workshops specializing in the Mercedes brand, where a combination of reasonable costs and original build quality is essential.

Technical support and knowledge about the fuel system

To better understand the role of the fuel pump in a modern car, its diagnostic methods, and selection by OEM number, it is worth using expert materials. A practical discussion on the construction and operation of the fuel system, along with tips on regeneration and maintenance, can be found in the article Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration.

Expanding repairs within the Mercedes fuel system

If you are planning a comprehensive repair or upgrade of the fuel system area in your Mercedes and need other components from the same group, such as in-tank pump modules, fuel level sensors, or complete supply units, check the available parts in the Mercedes fuel pumps and level sensors category.

Summary

Mercedes ML W166 GL X166 Fuel Pump Tank Fuel Sender Unit Petrol is an original, used fuel system component designed for in-tank installation. It ensures proper engine supply and reliable fuel level readings, and thanks to its factory-spec Mercedes design, it is a technically safe choice for repairs and upgrades of the fuel system in these models.