Sagara09

iTrader: (1)

I bought my civic with a B16A2 swap already done. He said it was a obd1 harness and my ignorance at the time didn't know the difference. Now that I have looked at the distributor plug wire and the injector plugs, it is clearly obd2. However, the car is running off a P2T ECU. What would be my best wiring harness to go with to allow the car to run healthy as possible?

As you may see, I am still a bit ignorant with this. I am still new to Honda's. I tend to stick with older Toyotas.

jbpnoman

I could be completely wrong here, and if I am someone please correct me.

The P2T is OBD2, from the EM1. The B16A2 is also from the EM1, as well as a few other chassis'. Assuming I'm right, and assuming the person who did the swap used the correct OBD2 wiring harness, everything was done like it should have been, wiring-wise. Are you having any particular problems? If you aren't, I think you're good to go.

Sagara09

iTrader: (1)

There is a jumper harness connecting the ECU to the wiring harness. Isnt the P2T OBD2B?

The car is running insanly rich and has some idling issues.

jbpnoman

I'm honestly not sure, I've never been a fan of OBD2.

According to this wikipedia article, the P2T ECU is the correct match with the B16A2. The only reason I can think there would be a jumper harness is if they used an OBD1 or OBD2A harness...what the hell, that sounds like a botch job to me.

Personally, if it was bothering me, I'd pick up the wiring harness for a 99-00 Civic SI and slap it in there. Your ECU and motor match - the only mismatched part is the jumper harness.

Also, as a side-thought, take a look at the jumper harness. Is it actually changing the pinouts? Can you unplug the harness and plug the pigtails straight into the ECU without any problems? I have two jumper harnesses in my car - one for OBD2A to OBD1, and one to splice in my sensors and ****. It's possible that's why they put the not-so-jumper jumper in there.

Try removing the jumper harness and plugging the harness straight into the ECU, and see if the car starts. Worst case scenario, you get a CEL and we know there's a janky wiring job there.

Sagara09

iTrader: (1)

The ECU is also a P2T-A11, if that helps. I will try to plug the ECU and the harness in. The ABC slots are filled while the D is empty as well.

jbpnoman

D being empty is normal. P2T-A11 is the USDM P2T, and the B16A2 is the USDM/CDM EM1 motor, so they still line up with each other.

Sagara09

iTrader: (1)

Not all of the plugs will fit. A and C are the only ones that have a change of a plug. The final plug from the harness is closest to fitting the D slot since it is a smaller plug.

tuned2

What year is your Civic? What trim level?

Sagara09

iTrader: (1)

It is a 97 Cx.

kyden

do you have a check engine light? is your engine harness one or two piece?

Sagara09

iTrader: (1)

I am getting a CEL but one of the O2 sensors is not plugged since the harness wont reach it.

kyden

there could still be other codes.

HondaPartsHero

Yeah check your engine codes and post them. It'll be at least a glimpse into your issue. Check my sig below if you need an extension harness for your 02.