Link G4X MX5Link MX5NAX ECU

The Link G4X MX5Link MX5NAX ECU is a direct-fit engine management system designed for early Mazda MX5 NA and BP engine applications. It installs into the factory ECU location and connects directly to the OEM wiring loom on supported vehicles.

This ECU is intended for manual transmission vehicles only and supports most factory systems while providing advanced tuning capability through the G4X platform.

Important: Manual transmission only. Designed for B6ZE(RS) 1.6L and BP 1.8L engines. Includes onboard 4 bar or 7 bar MAP sensor. Knock control is not available on this ECU. E-throttle requires modification before use. Please confirm your ECU connector matches the header shown in the product images before purchase.

Engine Control Capability

• Designed for B6ZE(RS) and BP 1.8L engines
• Sequential fuel injection
• Digital triggering using OEM patterns
• Staged injection support

Hardware and Platform

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

Vehicle Compatibility

• Mazda MX5 NA 1.6L (1989–1997)
• Mazda MX5 NA 1.8L (1989–1997)
• Mazda 323 GTX 1.8L
• Mazda 323 GTR 1.8L
• 2-plug ECU only
• Manual transmission only

Exclusions: Does not fit NB, NC, or ND MX5 models. Not suitable for later 3-plug ECUs.

G4X Plug-In Key Features

• Up to 6D fuel and ignition mapping
• Sequential fuel delivery
• OEM idle control supported
• 5D boost control with three switchable tables
• Launch control, anti lag, and flat shift
• Individual cylinder fuel and ignition correction
• Gear-based fuel, ignition, and boost compensation
• QuickTune automated fuel tuning
• Selectable dual fuel, ignition, and boost maps
• CAN communication support

I/O Expansion

Expansion Connector 1

• SGnd – Sensor ground
• +5V – Low current +5V supply
• DI7 – Digital input
• DI6 – Digital input
• Volt 5 – Analogue voltage input (0–5V)
• Volt 6 – Analogue voltage input (0–5V)
• Temp4 – Temperature input
• Temp3 – Temperature input

Expansion Connector 2

• SGnd – Sensor ground
• +5V – Low current +5V supply
• Ign 7 – Auxiliary output
• Ign 8 – Auxiliary output
• DI8 – Digital input
• DI9 – Digital input
• Volt 9 – Analogue voltage input (0–5V)
• Volt 10 – Analogue voltage input (0–5V)

Downloads and Resources

• Installation Manual (PDF)

View all Link ECU Resources