BMW G01 G02 G05 G20 Fuel Tank Breather Line Hose 3.0 Petrol M40i B58D 8664930

BMW G01 G02 G05 G20 Fuel Tank Breather Line Hose 3.0 Petrol M40i B58D is an original crankcase ventilation system component designed for BMW 3.0 petrol engines in M40i versions with the B58D unit. This hose, belonging to the Lines, hoses and pipes category, ensures proper discharge of vapors from the crankcase, which promotes stable engine operation and reduces the risk of improper engine ventilation.

Specifications and technical data

• SKU: 8664930
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8664930
• Substitutable numbers: 13908664930, 8664930
• Fuel type: Petrol
• Part type: Line
• Category: Hoses, Lines & Pipes

Purpose and function of the breather line

The breather line in the 3.0 M40i B58D petrol engine is responsible for the controlled discharge of oil and fuel vapors from the crankcase into the intake system. A properly selected component:

• stabilizes pressure in the crankcase during engine operation,
• limits the amount of excess oil entering the intake,
• supports smooth engine operation across the full load range,
• reduces the risk of leaks caused by overpressure in the system. For modern BMW petrol engines, using the correct breather line is essential for stable operating parameters, idle quality, and the proper functioning of mixture control systems.

Construction and fitment for the 3.0 Petrol M40i B58D engine

The offered line has been designed specifically for M40i B58D units, which means it features matched geometry, the correct internal diameter, and a shape adapted for routing within the engine bay. As a result:

• installation is performed at factory mounting points,
• the correct routing path relative to other components is maintained,
• the risk of rubbing against other parts and resulting damage is minimized. Precise fitment to the specific engine configuration translates into seamless integration with the existing ventilation system and the maintenance of factory flow parameters.

Performance characteristics of the used component

The line comes from disassembly, meaning it is a used part, but still intended for further service. This type of part allows for an economical repair of the ventilation system while maintaining the original BMW specification. In practice, this means:

• retention of the factory shape and rigidity of the line,
• compatibility with standard engine fittings and connectors,
• the ability to replace a damaged or leaking component without interfering with other parts. For users who want to restore the proper operation of the ventilation system without using aftermarket replacements, the used breather line represents a technically sound compromise between cost and compliance with the factory design.

Importance for petrol engine durability

A functional breather line in a petrol engine has a direct impact on:

• reducing deposits in the intake system and on intake valves,
• stable vacuum and pressure values in the crankcase system,
• reducing the risk of oil leaks from seals and gaskets,
• proper operation of the emission control system. In the case of 3.0 Petrol M40i B58D units, maintaining the ventilation system is particularly important due to the high power density and advanced design. Replacing a worn or cracked line with a functional component helps maintain stable engine operating conditions in the long term.

Integration with other BMW lines, hoses, and pipes

The breather line works in conjunction with other intake and ventilation system components, forming a cohesive system of lines, hoses, and pipes in the engine bay. If you are planning broader maintenance in this area, it is worth considering checking the condition of other flexible connections to avoid leaks and fuel-air mixture problems. If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other parts from the same group, such as vacuum lines, ventilation hoses, or intake pipes, check the available parts in the BMW lines, hoses and pipes category.

Technical support and project development

When planning upgrades or servicing systems in modern cars, it is helpful to use reliable technical and comparative materials. In the context of analyzing design solutions, selecting used parts, and planning modifications, it is worth reading an article describing the evolution of one of the popular compact segment sports models, available here: Hot-hatch legend: the evolution of the VW Golf GTI from Mk1 to Mk8 – design changes and VW car parts.