got a CRX with a 1st gen b16a with 2 o2 sensors both wired in to the ecu
ok i have code 2, o2 sensor, the CEL comes on everyonce in a while, especially when im hammering kinda hard on the motor and driving fast. Now this problem is popping up more and more. U guys think my o2 sesor is bad? or the wiring?Exhaust clog?
Also which slot on the ecu is o2 #1 and o2#2, ive review b16a crx shop manuals and found nothing, and which o2 on the header is #1 and which one is #2, i mean the cyclender #1 and #3 or #2 and #4

And if i replace the o2 which ones (year of honda) for a crx with a 1st gen b16a?

thanks for any help

 

I'm having this exact same problem but with the first o2 sensor, it wont go CEL unless you push on it, or go into high RPMs. Ok from what I've read you can tell the o2's apart as follows. If you look at the O2 sensors there is a green plug one and a white plug one. The white plug one is the primary o2, the green plug one is the secondary. The secondary is the wire you add so the green plug one should go to pin C8 from what I understand. I think I'm going to try and buy a Bosch o2 sensor tomorrow and see if it fixes it. Do you have any other problems like stubmling around 3k, surging idle, or hesitation under light throttle?

 

yeah mine hesitates too, and when it idles there is some surges and around 3k mine cuts out one in a while, i wounder if the o2s are reversed?

i might try that

 

The green plug is the o2 on the tranny side, and is the one you added. The o2 sensor on your crx harness is white, and should just barley reach to the crank pulley side of the engine. Most people switch them up, because it reaches easier if they are crossed. So make sure they are in the approperate spots, and check wiring, then trouble shoot the sensors themselves, check for approperate voltage. I had mine x-ed, and it made a world of difference. Ryan

 

Ok I replaced the o2 tonight, it took about an hour to do with air tools and the correct tool for removing the o2 sensor. I reset the ECU and let the new o2 set some good maps. After that I took it out on the streets, I can go all through VTEC up to any RPM with no check engine light. I do however still have hesitation under partial throttle but I'm not complaining.

 

are both of the o2s the same, do i just get 88-91 crx si o2 sensors, how do i check the voltage?

 

I believe they are all the same, I asked for a 91 Integra, basiclly you are just looking for a universal one wire o2 sensor. I bought a Bosch but I've heard many mixed opionons on how long they last.