hatchedlsvtec

So I put a 91 integra ls motor in a 91 civic si, then I swapped the head for a 95 gsr. I have a CEL 41, o2 sensor circuit malfunction. The car is made for 1 wire o2, but the ecu for the head requires a 4 wire o2. At first I kinda guessed on how to wire it, and of course I was wrong. If the sensor is not wired correctly, will it be damaged if used? Anyway I got an answer from a previous thread about where in the ecu the 4 wires go, but after connecting them all correctly i still have check engine light. Even after leaving battery disconnected for 1 hour and 1/2. Right now it is wired:

black o2 wire, sensor signal -- D18

gray o2 wire, o2 ground -- D22

white o2 wire, heating element -- A6

white o2 wire, heated signal -- D14

If this is wrong, it'd be tight to know. It sucks having Paid and worked for vtec and, just not have it. Also, the ground wire from the vtec pressure switch is just connected to the motor... it's a ground connection, but does it need to go to a ground in the ecu? Any info is awesome
Thanks

Rtsvtec2004

first off im curious why you had to change the ecu with the head what was different ?

hatchedlsvtec

I had a pr4 90-91 integra ls ecu running the ls head. Since LS is Non vtec, I had to get an ecu to run the vtec on the 95 gsr head because I don't know much about reprogramming computers. Also, I understand that obd-1 ecu's can run higher performance than obd-0.

hatchedlsvtec

The instructions that came with the o2 sensor said that since there is no polarity in the two white heater wires, they can be connected either way.

hatchedlsvtec

Hey some good old fashioned logical thinking. I'll do that and post if it works tomorrow thanks guy

hatchedlsvtec

Well damn I switched the white wires and started it, I could definately tell it started faster and easier than before, but the cel still came on. So I disconnected the negative cable from the battery for about an hour, cel Still on. 4 long blinks and 1 short blink, 41. Starts and runs, I'd say, better than before And it fixed the minor sparratic idle It had goin on. Could the sensor be bad now? I'm sure it may be possible but I'm not really tryin to buy another one for 75 arms and legs.

hatchedlsvtec

I checked continuity from the o2 wires to the end of the pins in the ecu connectors, found that the ground wire wasn't actually connected to D22, but there was continuity from o2 ground wire to a number of pins in the A and C connectors. I spliced the ground wire into D22 for connection. Other 3 wires proved correct continuity. CEL after 5 seconds running, codes 41 and 20, electric load detector. after leaving battery disconnected for hour, Demonic cel still on, just code 41.