Hondata

when i datalog my car the A/F reads 10.7 and doesn't change. when i have the car in ignition 2, it'll read 14.7. when i start the car, it immediately changes to 10.7. the o2 sensor reads 0.00 volts. its not throwing any error codes. i had a bad o2 sensor at first and the car ran like crap so switched it with a good one and the car runs 10x better with the new o2 sensor but still don't get anything besides a reading of 10.7. when the o2 is unplugged it'll throw a code and run like crap. so the o2 sensor has to be working??? but why won't it get a reading. at one point i did get a reading for about 10 seconds before it stopped working again.

have tried changing multiple o2 sensors off other k swapped cars known to be working, used a different ecu that is known to work and read A/F, have rewired the o2 sensor, change the wiring from the harness to the o2, change the plug on the o2 sensor, changed the relay for the o2, wired the o2 directly to the plug on the ecu. basically i'm all out of ideas. any help would be greatly appreciated

car is a 92 civic with a usdm k20a2 using a hybrid harness.

You either have a bad sensor or faulty wiring. Try using your K-Pro/ECU in a known good RSX or Civic Si and i'm sure you will get a good reading.

any idea where the faulty wiring is exactly?

Basically it is a matter of getting the manual and ETM (electrical troubleshooting manual) for the RSX, and then working through the troubleshooting section for the o2 sensor.

The usual procedure is to check each wire in turn for continuity from the o2 plug to the ECU, check that the wire is not shorted to ground, power or any other wire.

The tricky part with an engine swap is that the relay setup from the RSX needs to be duplicated exactly, otherwise you will get problems.

This diagram http://www.hondata.com/images/k20awiring.gif may help you, but you really should get both the helm and ETM for an engine swap.