Link G4X BMW M50 Plug-In ECU

The Link G4X Plug-In ECU for BMW E36 M50TUB25 is a direct-fit engine management system designed for vehicles originally equipped with the Bosch M3.3.1 ECU. It installs into the factory ECU enclosure and connects to the original wiring loom on supported vehicles.

This ECU supports both manual and automatic transmissions and is intended only for engines using the M50TUB25 engine code.

Important: This ECU is only compatible with the M50TUB25 engine using the Bosch M3.3.1 factory ECU. Please confirm your ECU connector matches the header shown in the product images before purchase. Electronic throttle requires modification before use.

Engine Control Capability

• Designed for BMW E36 M50TUB25 engines
• Sequential fuel injection
• Digital triggering with OEM trigger patterns
• Staged injection support

Hardware and Platform

• Direct plug-in installation using the factory ECU enclosure
• Onboard 4 bar or 7 bar MAP sensor
• Continuous onboard barometric correction
• USB tuning connection
• 512 MB onboard data logging

Vehicle Compatibility

• BMW E36 chassis
• M50TUB25 engine only
• Bosch M3.3.1 factory ECU
• Manual and automatic transmissions supported

Key Features

• Up to 6D fuel and ignition mapping
• Boost control with multi-dimensional tables
• Launch control, anti lag, and flat shift
• Individual cylinder fuel and ignition trims
• Knock control with windowing
• Selectable dual fuel, ignition, and boost maps
• Gear-based fuel, ignition, and boost compensation
• QuickTune automated fuel tuning

I O Expansion

This ECU includes a dedicated expansion connector. Expansion inputs and outputs are available using the Link expansion cable as outlined in PC Link documentation.

• TEMP3 – Temperature input
• TEMP4 – Temperature input
• VOLT4 – Analogue 0–5V input
• VOLT5 – Analogue 0–5V input
• DI7 – Digital input
• DI8 – Digital input
• +5V – Low current sensor supply
• GND – Sensor ground

Downloads and Resources

• Installation Manual (PDF)

View all Link ECU Resources