CEL 2ndary 02 pls help!

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r1paniccia

New Member
ok so i bought a 96 ek b16a2 swap p72ecu. car has a cel on for secondary 02 sensor. the primary is still hooked up, but there is no 2ndary hooked up, how do i hook this up ? do i have to tap into the ecu wires? there is a bung on the exhaust for a 2nd one just no were to plug it in! i really wanna get the cel off so i can pass inspection befor i turbo it. new york state is a pain in the butt with this! btw the prev owner gave me a 4 wire 02 sensor i just dont know where or what to do with it! any help is appreciated guys im clueless with this. i have searched and searched and cant come up with anything!
 
Technically, you should have wires that have a plug on the end to accept the secondary O2.
 
:concur:

its an OBD2 car, there is a plug under there for the secondary O2
get under there and look around
 
there is no wiring under there for the secondary 02. there is a primary 02 hooked up on the cat but there is NOT one after it this is what i need. just need to know how to wire it in
 
What wire harness do you have? If its off the EK......it has wiring for the secondary O2. But I don't know the history of your car. The secondary O2 wiring just may be cut somewhere. But maybe you got lucky and its tucked away in near the firewall or maybe under the carpet near the ECU?
 
What wire harness do you have? If its off the EK......it has wiring for the secondary O2. But I don't know the history of your car. The secondary O2 wiring just may be cut somewhere. But maybe you got lucky and its tucked away in near the firewall or maybe under the carpet near the ECU?

the previous owner said he used a 96-98 ex harness i beleave? he said it made the swap easier?
 
That harness definitetly has 2 O2 sensor plugs. But if he ran a OBD1 ECU with a jumper harness (lke a chipped P06 or P28) then the O2 wiriing may have been cut or tucked away b/c it is not needed with a OBD1 ECU
 
Once again.......it is not about being "wired in" I am 100% positive that a 96-98 EX harness has two plugs for 2 O2 sensors (primary and secondary). This became standard when OBD2A came out in 1996. 96-98 EX is a one piece harness form the sensors on the motor/trans/exhaust all the way through the firewall and into cabin which leads into the ECU (OBD2 P72)

So, once again, the only way that yours is not there is it was cut or it has been tucked away. Or the previous owner lied/didn't know and you have a non-OBD2 harness (like OBD1 or OBD0)
 
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