Harness Modification - SVX 3.3L

Harness Modification - SVX 3.3L

In stock

After completing over 2000+ harnesses for Subaru conversions, we are pleased to offer this wiring harness modification service that allows your Vanagon to confidently and reliably run a Subaru powerplant!

With every harness we run a basic functionality test, checking for correct main and fuel pump relay operation. All wires to the vehicle are clearly marked and the alternator and A/C (if applicable) wires are tagged.

OBD2 harnesses include our interface board to help eliminate 7 fault codes common on these installations. Please note that some codes, for example with automatic transmission harnesses, may still be present - although they do NOT affect engine performance or operation.


This Harness and ECU modification is for the following Subaru engines:

  • Subaru SVX 3.3L


Please keep in mind:

  • This item includes the harness modification as well as an ECU to eliminate the Immobilizer and for utilizing SCP’s Speed Sensor
  • All the engine management functions are fully operational, including variable valve timing.
  • We recommend that the electronic pedal be mounted near the engine so the wire length to that sensor is suitable for that location.
  • All harnesses are rebuilt to allow the ECU to be placed in the stock location ('86-'90) under the rear seat. For '80-'85 Vanagons they can also be installed there.
  • ’86-’90 Vanagons will need a modified tachometer.
  • Please allow up to four weeks after we receive your harness for completion. A harness received without an ECU will have the arrival date defer to the date the ECU arrives.


Ready to modify?

  • Fill out and return your Harness Modification Request.
  • Make sure to tell us what type of speed sensor you will be using. If you choose to use SCP’s speed sensor, we can prewire your harness.
  • When you send in your harness, please include the main relay, fuel pump relay, throttle control relay, oxygen sensor/air flow relay and ECU. These are essential for us to do a functionality test on your completed harness.


We regret that we can no longer accept harnesses that have already been partly modified by someone else.