Subaru Impreza WRX / STI standalone ECUs
Subaru's turbocharged all-wheel-drive Impreza, launched in 1992 with the boxer EJ20 and later EJ25 engines, and raced in the World Rally Championship.
- Chassis
- GC8 to VB
- Years
- 1992–on
- Engines
- EJ25 (per Link) · EJ257 · EJ25 · EJ20 · EJ207 · EJ20 / EJ25 turbo
- Layout
- 4-cylinder, AWD
You have 31 plug-in ECU options for the Subaru Impreza WRX / STI from Link, Haltech, MoTeC, Emtron, ECUMaster, Syvecs and rusEFI, 15 of them direct plug-in. The cheapest complete setup is rusEFI at US$460 including the ECU. 63 wire-in ECUs can also run its 4-cylinder engine with a custom loom, from US$155.
Prices checked and include the ECU.
Your options for this car
New to this? Three ways to fit an aftermarket ECU explains each one in five minutes.
Dedicated plug-in 15
Built for this car. Goes where the factory ECU was and plugs straight into the factory loom.
From US$1,525 →
Standalone + adapter harness 16
A general-purpose ECU with an off-the-shelf harness that joins it to the factory ECU plug.
From US$460 →
Wire-in ECU 63
Any ECU with the right features, on a new or rewired loom. Best for race cars, swaps and big changes from factory.
From US$155 plus loom →
Reflash
Keep the factory ECU and rewrite its tune. Usually the cheapest, keeps every factory feature, but limited to what the factory hardware can control.
Reflash options for this car are still being checked.
Plug-in ECUs for the Subaru Impreza WRX / STI
31 options, cheapest first. Each one links to its full specs and sellers.
Subaru Impreza WRX / WRX STI 135-pin Superseal Adapter
OEM-connector to 60/26-pin Superseal adapter board for a Superseal-connector rusEFI ECU (ECU not included)
WRX2X Plug-In ECU (Subaru WRX & STI V1-2)
Manual (auto: contact reseller); IAT sensor highly recommended; E-throttle needs modification
WRX4X Plug-In ECU (Subaru WRX & STI V3-4)
Manual (auto: contact reseller); IAT sensor highly recommended; E-throttle needs modification
WRX6X Plug-In ECU (Subaru WRX & STI V5-6)
4 grey-plug ECU; manual only; IAT sensor highly recommended; E-throttle needs expansion loom
HT-150941 Elite 1500 + Subaru WRX MY93-96 & Liberty RS Plug 'n' Play Adaptor Harness Kit
Manual only
WRX104X Plug-In ECU (Subaru WRX & STI V10, 2004-06)
Subimods lists fitment as 2006-07 USDM WRX; Manual only; built-in E-throttle; for cars whose OEM connector pins A1-A3 are populated (else WRX107X) Subimods lists fitment as 2004-07 USDM STI; Manual only; built-in E-throttle; for cars whose OEM connector pins A1-A3 are populated (else WRX107X)
WRX107X Plug-In ECU (Subaru WRX & STI V10, 2006-07)
Late-2006 and 2007 models; Manual only; built-in E-throttle; for cars whose OEM connector pins A1-A3 are empty (else WRX104X)
WRX9X Plug-In ECU (Subaru WRX & STI V7-9)
5-plug ECU; manual only; E-throttle needs expansion loom
USDM WRX11X Plug-In ECU (Subaru WRX V11, USDM)
USDM pinout; manual only; built-in E-throttle; IAT sensor highly recommended; supports DCCD, SI-Drive, cruise FA20 WRX not supported; USDM pinout; manual only; built-in E-throttle; IAT sensor highly recommended; supports DCCD, SI-Drive, cruise
WRX11X Plug-In ECU (Subaru WRX V11)
Manual only; built-in E-throttle; IAT sensor highly recommended; immobiliser lamp may stay lit USDM cars with common international Denso pinout; Manual only; built-in E-throttle; IAT sensor highly recommended; immobiliser lamp may stay lit Per Subimods fitment listing; Manual only; built-in E-throttle; IAT sensor highly recommended; immobiliser lamp may stay lit
HT-151320 Elite 2500 + Subaru WRX MY06-07 Plug 'n' Play Adaptor Harness Kit
Not compatible with Hitachi ECU
HT-151321 Elite 2500 + Subaru WRX MY06-10 Plug 'n' Play Adaptor Harness Kit
ADM only; not USDM; not Hitachi ECU
HT-151325 Elite 2500 + Subaru GDB WRX MY01-05 Plug 'n' Play Adaptor Harness Kit
All regions; manual only Manual only
Subaru Impreza 1992 to 2005 – Direct Fit ECU (S7)
Listed for GC/GF; Board fits inside OEM ECU case (no case supplied); AVCS and DCCD supported
Subaru Impreza 1992 to 2005 – Direct Fit ECU (S7)
Listed for GC/GF; Board fits inside OEM ECU case (no case supplied); AVCS and DCCD supported Board fits inside OEM ECU case (no case supplied); AVCS and DCCD supported
HT-213310 Nexus S3 Plug 'n' Play Adapter Harness Kit - Subaru GDB WRX MY01-05
All regions; manual only Manual only
HT-213311 Nexus S3 Plug 'n' Play Adapter Harness Kit - Subaru WRX MY06-10
ADM only; not Hitachi ECU
HT-213312 Nexus S3 Plug 'n' Play Adapter Harness Kit - Subaru WRX / STI MY11-19 (Australian Delivered Models Only)
Australian-delivered only; manual; WRX GV/GR excl. 2013
2015-19 Subaru WRX M142 Kit
MoTeC USA kit (not on motec.com.au targeted list); Integration patch harness; GPR-DI based
2022 Subaru WRX M142 Kit
MoTeC USA kit (not on motec.com.au targeted list); Integration patch harness; USA Drag DI based
EMU interconnector (Impreza)
MY96-98; Listed as available interconnector on ecumaster.com; no US store listing found
Subaru Spec STI 2015 M1 Package (licence #23202) + Subaru Adaptor Loom
Package for M150; optional Subaru adaptor loom gives no-rewire install; paddle-shift package 23203
No plug-in is listed for that chassis and year. A wire-in ECU below will still fit with a custom loom.
Wire-in ECUs that can run this engine
Cheapest current unit from each brand with at least 4 injector and ignition outputs, so it runs fully sequential.
Add a loom: built by your tuner or a loom maker. Filter every wire-in ECU by features and price
Find a tuner for these ECUs
Shops with their own dyno that tune the brands above.
About the makers: Link · Haltech · MoTeC · Emtron · ECUMaster · Syvecs · rusEFI