Thread: o2 issues..

Mornin all,

Just having some issues with my car (96 200sx SER) after installing a new turbo setup.

Here's the problem:

Car air/fuel ratios at idle 11.7-12.1 according to the LC1 wb

Old O2 sensor, stuck on 0.3V

Here's what we did/tried:

Got a new O2 Sensor, from Nissan Dealer, still showing 0.3V (tested between ECU pin 43 and ECU pin 46, also same on the Nissan Data Scan) from start up and continues after engine is fully warmed up.

Nissan Data Scan shows O2 always "rich" does not cycle between rich and lean.

O2 sensors harness test results, which are OK according to FSM:

O2 harness Pin 3 to ground shows battery voltage with ignition on
O2 harness Pin 2 to ECU pin 46 has continuity
O2 harness Pin 2 to ground, no continuity
ECU Pin 46 to ground, no continuity
O2 harness Pin 1 to ECU pin to ECU pin 115 has continuity

Only test which does not show proper results according to FSM:
ECU Pin 115 to ground, always shows 0.01V, FSM says it should be about 0.2V at idle and battery voltage above 3200rpm.

What could be the problem? What should we test?

What ECU are you running?

JWT ECU reflashed for the new setup.

Where is the O2 sensor installed on this setup?
Maybe it's not getting a good ground.
3 wire sensor grounds through the housing.

You could get a universal 4 wire sensor and run a dedicated ground wire.
This is the one I used with my stainless HS gen6 header:
Amazon.com: Bosch 15727 Oxygen Sensor, Universal Type Fitment: Automotive

Thanks for the response..

o2 sensor is installed on the DP approx 7" from the backhousing of the turbo.

When we were constructing the DP we didnt have access to a proper o2 bung. So we had to use a SS Nut that fit the o2, we then welded that in place.

We tried to wrap some 8 gauge wire around the sensor as we screwed it in and grounded it to the chassis, but this did not help. Maybe it didnt make a good contact?

I would try the universal 4 wire and wire the ground to the head.

Brent

^ cool

ordered the sensor thanks jP. Should have the sensor in my hand on friday so I'll try it out and let you guys know.

Thanks again

Moved this to the Turbo Section.

More info on the 4 wire deal here.

Where is the fuse for the front O2 sensor Heater located?

+1^

Does anyone know where we can find this?