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O2 Voltages In Gtr

Pal

By Pal,
in Engines & Forced Induction

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Pal Veteran

Pal

Posted
Posted

hey guys

just replaced my o2 sensors but from what ive read, i think something maybe wrong. o2-1 reads a .8 to .9v at idle. o2-2 sits on .06v. ive given it a bit of a rev and they both move but i would think they should be the same voltage.?? i used the rb25 (NTK OZA395-E2) *2 with plug modification

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rob82 Mentor

rob82

Posted
Posted

hey guys

just replaced my o2 sensors but from what ive read, i think something maybe wrong. o2-1 reads a .8 to .9v at idle. o2-2 sits on .06v. ive given it a bit of a rev and they both move but i would think they should be the same voltage.?? i used the rb25 (NTK OZA395-E2) *2 with plug modification

GTR's trim the front 3 and the rear 3 cylinders independantly so they will neverread the same while in closed loop.

Moodles2 Grand Master

Moodles2

Posted
Posted

I'm not sure if I would trust either's voltage output, when fully warming up at idle you should see 0.4-0.6v.. but if they are indeed working then the first 3 cylinders are running rich (assuming o2-1 is the front sensor), while the last 3 are running lean

rob82 Mentor

rob82

Posted
Posted

They will only really trim once its hot and on cruise. Try bringing the revs up to 2500rpm hot and see what you get - if one goes lean and the other rich - then you have most likely wired them around the wrong way (the best check is to watch the fuel trims as you will see one go to full positive trim(25%) and the other to full negative trim(25%)). ie front 02 signal in the rear dump and rear 02 sensor in the front dump.

Pal Veteran

Pal

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just give it a rev to 2500. 02-1 sits on .9 to 1 v. o2-1 sits on .08 to .09.

checked the wiring, long plug goes to back, square plug goes to front (can someone confirm this please)

wires are in correct positions(same color wires go to heaters and same to signal wire across to plugs)

where do i see the fuel trims?? had a look in the screen for o2's and couldnt see them there

Pal Veteran

Pal

Posted
  • Author
Posted

just went through my pfc screens and it turns out the o2 f/b control was turned off. there is another one, 02 sensor reg. does this need to be turned on too? must be a gtr thing cause i cant find it in any manuals

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