ok so i have a 97 civic dx hatchback w/d16y7
donor car 96 civic ex sedan

took the y7 out and installed the y8 how do i wire the 02 sensor?
i have a brake light(on the dash) on until i hit the brakes

 

Low brake fluid in reservoir?

Are you asking how to lengthen the four wires?

 

I checked the brake fluid. i has to be something to do with the brake switch, or going from I cant put the car in gear without something stuck in the release by the shifter.

as far as the 02 sensors the y7 had the cat on the header so the second 02 sensor was right by the transmission. both were in the engine harness. the y8 out of the 96 had one 02 sensor by the header and one close to the shifter, that one is connected to the dash harness, so on my car side i dont have that plug. its not about extending wires at this point, i just dont have the plug.

 

The donor car had a Y8 with a secondary O2 sensor. The header on your old Y7 had a secondary O2 sensor. Your current engine has the mate connector for either of the latter O2 sensor plugs. What am I missing?

 

Using an EX engine harness in a CX/DX/LX will leave you with no secondary O2 sensor plug as it is part of the cabin harness on the EX.

You have 2 options:

1. manually add the missing 4 wires and pin them into the appropriate locations using a wiring diagram for a '96 EX
2. Use the EX cabin harness, it will plug in and you can swap all the power options from the EX over if you want to this way

 

Haha...The thread comes full circle. This^ is basically the earlier mentioned wire extension solution (and easiest solution) requiring a couple of the original Y7 ECU connector wire pins and the original Y7 O2 sensor plug with its attached wires. Comprende?

 

thank you guys for all the help.