Recently I picked up two second gen outbacks, hoping to swap the engine & drivetrain from an 02 with 150k mi to a much less rusty 04 with 300k mi. Since Subaru added EGR sometime in between these two cars, I figured I had two options: drill and tap the head for the EGR port, or swap the ECM and wiring harness. For some godforsaken reason, I thought swapping the ECM and wiring harness would be the better way to go.

That was a ton of work, and I ran into a bunch of mismatched connectors. Instead of pausing to check my options, I doubled down and just kept swapping harnesses until I ran out of mismatched connectors. This wasn’t too technically challenging but took a ton of time.

Luckily, when I hooked the harnesses back up, the engine fired right up. Unfortunately, the airbag and ABS lights are both on. I think there’s a missed connection somewhere from hooking the 04 sensors up to the 02 harness. I‘ve tried to troubleshoot a bit but havent gotten anywhere.

I think I know what I need to do: backtrack, reinstall the original harnesses, and just swap the intake over with the EGR valve. This is mostly a rant, but maybe it’ll help someone avoid getting bad tunnel vision like I did. I didnt start this project because it’s easy, but because I thought it would be easy lol