wiring a b17a for obd0 setup

ASSISTANCE Hybrids & Advanced Aftermarket Engine Performance
1

i swapped a b17 gsr into my 90 integra and have ru n into a slight issue i have an obd0 pr3 ecu and was wondering where does the 2nd o2 sensor go i have o2 sensor bungs on the cat but ive been looking and ive found multiple sites saying that i need a second o2 sensor on my header because the o2 sensors monitor air fuel ratio for each pair of cylinders and the pr3 ecu tunes fuel for each pair of cylinders…so wat is the right way for the placement of the o2 sensors

2

B17a is obd1 and only has one o2 sensor, other then that get a obd1 harness and p28 ecu would make life a bit easy

3

jdmprojectz you are correct. The two o2’s on a pr3 monitor cylinders 1&4 and 2&3.

You basically have two options:

  1. get a 2nd bung welded into the header (like this, as you can see each o2 bung monitors the correct cylinders)

  2. get the ecu chipped and have the 2nd o2 disabled (this is what I have done)