Hey guys, hoping not to get roasted, just need an answer to my question. So I have a 1999 Honda civic coupe si and this weekend I swapped in an ls non vtec b18b1, got everything finished expect for the wire harness... Do I need to use a D series wire harness with an obd2b-obd2a jumper harness? Because I have the b18b1 wire harness on, and nothing connects to the p75 ecu (the car is obd2b and the engine and ecu I swapped into the car is obd2a) and I have a few wires that don't connect to anything? Please help, this is my first ever swap and I just need some help to get her running! Thanks in advance!

 

No. YOu didnt' specify what obd ecu.

 

I fixed the thread, but the car is obd2b and the b18b1 and p75 ecu is obd2a, so I'm wondering, do I use my old D series wire harness, and then buy an obd2b-obd2a jumper harness so the D series wire harness (obd2b) can connect to the p75 ecu (obd2a)???

 

Whats wrong with using the current engine harness in the car? Is this an em1?

 

If your car is a true 99-2000 Si (EM1), then your stock harness can be used. But yes, you will need a jumper harness to use the OBD2a ecu. eBay has some for around $85.

The distributor is another issue:
OBD2a: 9-pins
OBD2b: 7-pins (no tach signal)

Easiest dizzy fix is to use a B series non-vtec OBD2a distributor.

Or, install (solder) an OBD2a connector onto your main harness and run 2 additional wires from the dizzy into the car.

See this pic for info on the pinout differences:
http://ff-squad.com/tech/wiring/obd1-2dizzywiring.jpg

 

It's not a true EM1, it's a Canadian Si, so it came stock with a D series engine. That's why I'm confused, because I can't use the b18b1 wire harness, **** doesn't line up, but the D series harness will line up with most things I believe, I would just need the jumper harness and do what you said for the dizzy

 

I did this swap & used the stock harness. It all worked perfect

 

Than you already have a d-series harness, all you need is to distributor adapter and the obd2b-obd2a harness. If you had the SiR harness everything would line up.

edit: you'll also have to repin the crank harness.

 

swapped a b20 into my 99ek hatch used the D series harness just had to attend and change a few plugs