Just ran all the cables for my swap through the left side fender and into the cab but they don't reach the engine components now. Am I doing something wrong?

 

I lengthened some and got the engine wires plugged in by lengthening some sensor wires but now I'm thinking maybe that wasn't a great idea as it may alter the resistance.

 

I also can't plug the o2 sensor in... Am I doing something wrong?

Did you make this harness?  From your post it sounds like you may have bought a pre fabbed harness.

Adding a little length as you did will do nothing to the resistance.  There's minimal resistance on those short runs of wire.  Absolutely nothing to be concerned about.

I work on wires daily that can be as long as 30,000 feet and are only 22 gauge at best and as small as 26 gauge.

Edited March 2, 201610 yr by firehawk618

IF you've got an OBD I harness, like 90-94 Legacy, you will have to lengthen or reroute some wire through firewall.

 

Origianlly in the Legacy the, Crank, Cam, and Knock sensor wires, as well as the O2 connector came through the firewall rather than with the rest of the bundle through the fender.

 

For all my swaps now I just use a 2" hole saw right through the fiewall and reuse a firewall grommet from the EJ harness.  run the whole bundle through there.  The spot where a RHD steering column would go is a good spot and then mount ECU behind Glovebox

I thought about mounting the ECU on the other side... Should have done that. Too much work to change now.

 

All good and running extended some sensor wires need to do both o2 sensors now.

 

Its obdii BTW.