I have a 90 civic ex w/b16 swap. I just fixed the distributor, ( to get rid of code #9) NOW I have code #2. what causes this please.
thanks guys.
Eric

 

Code 2 is the (O2B) Oxygen sensor. You either have:
- a unplugged O2 sensor.
- a broken wire from the O2 sensor B to the pin C8 on the ECU C plug.
- a unshielded wire that is picking up EMP from another wire. (very common in getto swaps)
- a bad O2 sensor.
- or a O2 sensor that is not in the factory location and not reading in the proper heat range. Remember that the JDM OBD0 ECU's needed 2 (two...meaning 1 + 1) O2 sensors that are reading cylinders 1 & 4 and 2 & 3.

Hope this helps.

 

damn. yeah Ill drive it for about 30 min on the interstate then ill slowdown, and "boing"
the ecu throws the code. but I dont have 2 o2 sensors, I have a megan racing header, + the motor is Obd1, just running it OBD0. thanks dude any more info could help.

 

oh yeah it is a pr3 ecu too.

 

PR3-PWO...Doesn't matter.

Both the PR3 and PWO need the two O2 sensors to run correctly. Many people will tell you that they only run one O2 sensor, but I'm telling you, as will the Hondata guys, that you should run both to get a PR3 or PWO to work the way it was designed to.
Also, the OBD0 non-heated O2 sensors are not suppose to place at the end of the header. They are suppose to be placed about where the oil dip stick sits. O2 sensor A needs to be in the #1 or 4 runner, and O2 sensor B needs to be in the #2 or 3 runner. A good muffler shop can weld the O2 bungs in for a little charge.

 

http://www.hasport.com/Products/Headers.htm

 

ok cool, so what ecu pins get the o2 sensors?
thanks dudes

 

For O2 sensor A...which is not your problem (code 1) canbe found on pin C16 on the C plug.

 

your so smart john, duh

 

Thanks mike, but I'm not a honda mechanic.

But I did sleep in a Holaday Inn Express.