p2p to p2t wiring differences

We may earn a small commission from affiliate links and paid advertisements. Terms

I will be swapping my ex(d16y8) to si(b16a2) on wednesday oct 23rd. I've looked at the plugs of the si's engine and ecu and compared them to my current ecu plugs. i have the entire si harness (from the engine to the ecu)and ecu.
are there any wiring changes i will have to make in the remainder of the car's existing harnesses?

thanks much :worthy:


the problem here is you have a car that is OBDII.a with a motor that is OBDII.b. Here is what i did to get mine to work (i have almost the same deal you do) i got a 96 EX harness (which obviously you have) plugged that into the b16a2 (you have to extend a few wires). i then got a P28 ecu (92-95 OBDI civic ex ecu) programmed to run a DOHC vtec motor. then got a conversion harness (got it off www.thepartstrader.com, there are many people who make their own and sell them, much cheaper this way, and they work the same.) this way i could plug the P28 ecu into the 96EX harness. this way is very clean, and no cut wires. if you try to use the SI harness, you run into problems because of the 2 different OBDII versions. hope this helps.. oh, if you use a reprogrammed P28, it usually disables the knock sensor and 2nd O2 sensor, so no need to wire those up.
thats the same advice i was going to give, well that or use your ex harness and modify it, but the SI harness is going to be nothing but a haeadache, you'd need to re-wire the dash or get a new dash harness