Throttle Body Assembly BMW M3 E46 Z4 M3 E85 E86 Petrol S54 Air Intake 7840422

Throttle Body Assembly BMW M3 E46 Z4 M3 E85 E86 Petrol S54 Air Intake is a precision intake system component, designed specifically for the high-performance S54 engines in M3 E46 and Z4 M3 E85/E86 models. As an original BMW part from the Throttle Bodies category, it ensures stable control of the air volume entering the petrol engine, which translates into predictable throttle response. This solution is dedicated to users who expect a proven design and the maintenance of factory engine performance parameters.

Specifications and technical data

• SKU: 7840422
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7840422
• Substitutable numbers: 7840422, 13547840422, 7832168, 13547832168, 7831799, 13547831799
• Fuel type: Petrol
• Category: Throttle Bodies

Purpose and function in the S54 engine

The presented throttle body assembly is an intake system component designed for S54 petrol engines used in the BMW M3 E46 and BMW Z4 M3 E85/E86. It is responsible for the precise metering of air to individual cylinders, which is crucial for power characteristics, torque, and idle stability.

Thanks to its design tailored to the specifics of the S54 unit, the throttle body assembly works with the factory engine control unit, allowing for the retention of stock injection and ignition maps. This solution is particularly important in cars used both daily and on the track, where a repeatable response to every press of the accelerator pedal is required.

Construction and technical characteristics

As an element from the Throttle Bodies group, the assembly has been designed for high operational stability across a wide range of loads and engine speeds. The construction is intended to work with the engine management system, position sensors, and the petrol fuel supply system, which allows for maintaining the correct air-fuel mixture throughout the entire rev range.

This solution is particularly beneficial in high-revving units, where fast and repeatable changes in throttle opening are required. Properly selected intake channel cross-sections and throttle plate geometry promote efficient cylinder filling, which supports engine performance without the need to interfere with the factory architecture of the intake system.

Practical application and benefits of installation

Installing the throttle body assembly in the S54 engine allows for the preservation of the factory engine characteristics, which is important both during repairs and when restoring a car to its original specification. Using an original BMW component limits the risk of adaptation issues, ECU errors, or unstable idle speed.

• retention of stock throttle response and predictable acceleration,
• compatibility with factory S54 engine equipment,
• consistency with the original control and diagnostic system,
• reduction of the risk of leaks in the intake system.

For users who drive their cars dynamically, stability at high RPM is also important – a properly functioning throttle body assembly supports the smooth operation of all cylinders, which promotes engine durability.

Component condition and installation aspects

The offered throttle body assembly is a used part, which allows for an economical repair of the intake system while maintaining the original BMW specification. Before installation, a standard service procedure is recommended, including checking connection tightness, verifying the mechanism's operation, and performing adaptation in the engine control unit according to the vehicle manufacturer's procedure.

A properly selected and installed throttle body assembly reduces the risk of problems such as fluctuating idle, power loss, or errors related to incorrect air-fuel mixture. This is especially important in high-specification petrol units, where the precision of air control has a direct impact on refinement and performance.

Expanding the intake system in BMW

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other components from the same group, such as additional housings, control modules, or elements working with the intake system, check the available parts in the BMW Throttle Bodies category.

For drivers interested in deepening their knowledge about the operation of fuel supply systems, diagnostics, and symptoms of injection faults, an article describing the symptoms and effects of improper injector operation in diesel engines may be helpful – you can find it here: diesel injector faults – symptoms, effects, and diagnostics. Although it concerns diesel units, it clearly demonstrates the relationship between the precision of fuel and air metering and engine stability.