Drive by Cable to Drive by Wire Conversion for Subaru
Updated: Aug 9, 2019
This blog post describes the basics of how to update cable throttle (drive by cable) to an electronic throttle (drive by wire) in a Subaru. Not sure if your car is cable throttle or electronic throttle? Check here. Unfortunately we can't give a full wiring write-up for this conversion since there are so many variations but we can list the step-by-step basics of what will need to be updated in the car.
It basically comes down to updating three components:
1. Updating the throttle body
2. Connecting the new throttle body to your ECU
3. Updating the gas pedal
Updating the Throttle Body in a Subaru
The cable for the throttle is attached to the throttle body which is attached to the engine. To update the throttle body in a Subaru is rather simple, it is attached to the new engine being installed. The other piece of this conversion is removing the cable for the throttle from the car which runs from the old throttle body to the old pedal. To do this, simply unbolt the cable by removing the clip that's attached to the pedal and the engine. Then pull the throttle cable out of the engine bay and into the car through the firewall grommet.
Connecting the New DBW Throttle to the ECU
If you've done a merge with iWire than you can skip this step and just plug the harness back into the ECU and the new pedal. If you went a DIY route, then wire up the DBW Relay to the ECU. We can't give specific pin information here because it changes so much between different car models and years. Find a diagram that is specific to your car's model and year for this information. Below are links to common DBW plugs needed for this conversion.
Updating the DBW Gas Pedal
To update your pedal you will remove the two bolts that currently hold it in place and then just pull it out. Then mount our iWire DBW Pedal Adapter Plate into place. (You'll want this bracket because the mounting points for the cable throttle pedal are different than the DBW pedal). Next just bolt the new DBW pedal onto the mounting plate and you're good to go. If you're more of a visual person we have posted our install video below.
Common Plugs Needed for Conversion: