so like we put a z6 into my buddies vx and the z6 that we got had the whole wire harness on it so we decided to use it.... but the wierd thing is, is that on the passenger side there are four plugs that go to the ecu and on the ex harness that came with the motor there are only three.... im an ef guy so this stuff kinda is confusing

 

the VX came with four on the passenger's side for the EGR and 5wire O2 setup that is specific to the VX.