Hello all,

I just finished swapping a d16y8 from a coupe into my 98 hatch DX. On my d16y7 the headers had the cat connected to the headers with 2 O2 sensors. On the new y8 headers, there is only 1 o2 sensor and no cat. I used a d16y8 engine harness(complete) and it has no plug for a 2nd o2 sensor. My car is throwing a P0141 (02 sensor heated curcuit) and I am sure that is why. I already intend to install a cat in the car but I am curious as to whether I will be able to plug and play the 2nd o2 or if i will have to hard wire it to the ecu. Do the d16y8 main engine harness not have the plug for the 2nd 02 typically?

 

use the other ecu or get a obd2 to 1 conversion and obd1 ecu and call it a day. no codes no need for cat or extra o2 sensor

 

I don't think the Y8 has the secondary o2 sensor plug. All it has is the one on the manifold. Are you still running your stock DX header? What ECU are you running?

 

in order to make this a complete plug and play, use the y7 harness anld extend the 2nd sensor wires. as the y8 dosent have it on the wireing harness for the engine.
in an ex, the 2nd o2 sensor wires through the chassis.
you will also have to modify the wires leading to the idle air controld valve as the y7 has a 3 wire and the y8 has the typical 2 wire.
this is a better way to go because if you ever decide to do an engine swap this is the one to have.
hope this helps

 

I am running the P2P or d16Y8 ecu which is why it interesting the 2nd o2 is not connected to the harness. Will this work:

Get a 2nd o2(and cat) from a EX and then run the wires and hard wire them into the ECU pins for the 2nd o2? If so, can someone point me to an ECU pinout for the odb2 P2P ECU?

 

its easier to bypass this or get a conversion harness. Unless u need the cat for emissions in ur state its worthless. I'm not sure exactly where the 2nd o2 sensor in the EX goes. I know i have one in my car but i have no idea where in the car it gets connected to the harness. It just comes out of the bottom of the car and goes into the cat and the wire goes up into the chassis somewhere.

 

I'm guessing you got the obd2a? here is pin out. Just run a wire up into the chassis and into the ecu, or you can just use your y7 headers, unless you have aftermarket headers than, your stuck rewiring it. Your giong to need a cat as they mention if you need emission anyways so find a 96+ex cat. Make life easier, cause it has a o2 bung on it.

http://www.ff-squad.com/technet/wiring.obd2a.htm

 

just drill a hole in the exhaust pipe. i had my local muffler shop make me a bung for $10. cuz im boosted a cat would just suck for me.