Easy to install. Affordable. Reliable.  
G4X PlugIn ECUs offer the latest in engine management technology, designed to easily maximize the potential from your car.  
This ECU fits inside the factory OEM enclosure. Installation of the processing unit is a breeze, with no alteration of the factory wiring loom required for the models listed below. 

Designed for the WRX V5-6 EJ20. 

• Please check your pinout matches the header in the listed photo before purchasing.  
• This ECU works for manual transmissions only.  
• Air temp sensor highly recommended. 
• Most factory features are supported. 
• Check the features tab for I/O input & output expansion options  

Note: V1.4 onwards of this Plug-in features a new 4 pin powered CAN connector and cannot use the old CANPCB cable for CAN connection.  Use the CANJST4 (Code 101-0198) cable for connecting CAN devices.  This new 4 pin port and cable provides not only the CAN connection, but also a protected 12V power supply and ground for powering the CAN devices.  The power supply is protected by a self-resetting fuse rated at 3A continuous. 

Suitable Applications for 228-4000 automotive computer unit:
GC8F 
GC8G 
WRX and STI from 09/1998 to 08/00 
MY99 & MY00