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 is a breeze, with no alteration of the factory wiring loom required for the models listed below. 

Designed for the WRX V10 EJ25. These ECUs cover 2.5L from 2004 to 2007. 
 

• Please check your connector matches the header in the listed photo and check the notes in italic below 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 expansion options  

Suitable Applications:
The WRX104X mostly covered the 2004-2006 range. 
The WRX107X (listed separately) mostly covers the 2007 model. 
 
However, some 2006 models require the WRX107X.
 
*The fastest and most reliable way to tell, is to check whether pins A1-3 are populated. 

*If the pins have wires, you need the WRX104X, if there are no wires, you need the WRX107X 

*Suits GD or GG chassis with electronic throttle.  Not suitable for the GR/GH/GE/GV hatchback or 3rd generation WRX’s