I've been searching for a long as time now and I mean like weeks long.

Car: 1992 Honda Civic DX
Engine: B16 SIR-2 (no wiring harness)
ECU: P30 OBD-1
Problem: I've been reading and reading about adding the necessary VTEC wires into my car. Some say: 1) My car is already wired for VTEC and it's just plug in play with the motor and ECU. 2) My car is already wired for VTEC, but only to the ECU and I will still need to add the wires from the engine to the plugs under the hood. 3) I will need a 92-95 EX/SI engine harness and plug those on my engine and to the connectors under the hood and there should be the VTEC wires already connected from there on to my ECU.
Solution:???

 

the one thing u have to do no matter what car u have, si, dx, cx, vx, or whatever. is u have to run the wire for the knock sensor, if u don't have the harness wich u don't, the best thing to do is either find one for your engine, the b16, or get a 92-95 si or ex harness, and run that on the motor instead, but regardless, u will have to run the knock sensor wire from the computer, to the plugs in the engine bay, but every car is wired for vtec from the ecu to the engine bay, however i have had, and heard of wiring probs with vx cars, they are just awkward.....

 

Yeah twisted hatch pretty much nailed it.

I'll add this:

I'm guessing you'll be running the DX engine harness, right? If so then...

The only VTEC wires you'll have to add will be from the actual VTEc solenoid and oil switch from the actual switches themselves to the plugs on the strut tower areas in the engine bay.

As Twistedhatch said the VTEC wires are already there from the underhood engine plugs on the car through the firewall and into the ECU plugs.

Had you been able to get the VTEC engine harness then you would not have to add any VTEC wires at all.

If you could run a re-chipped P28 ECU and the VTEC engine harness then you would not have to add one single wire at all - I didn't have to add a single wire for my B18C5 swap into my 1992 CX because I used the B18C5 engine harness and re-chipped P28 ECU.

Plug and play is nice, but you can add a few wires - it's not rocket science.

Good luck!