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R34 GTT o2 Sensor Replacement

satanic

By satanic,
in Engines & Forced Induction

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satanic Grand Master

satanic

Posted
Posted

Hello

I know that there is some killer thread out there with all of this info on o2 sensors... but the point of this question is if there is a specific part for the 34 GTT or does the Ford EL work on that too? Most of the guys there were talking about 33 or 32 sensors and not the 34.

I'm gettting about 350kms out of a full tank with no pretty much stock gear (panel filter from k&n + boost at 10psi) - car has 40k kms clicked on it, should I be looking to get a new o2 sensor?

Any help or direction to specific parts would be most appreciated~

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satanic Grand Master

satanic

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I'm going to get my exhaust fitted today; will ask about the fuel economy and whether or not it'll be a good idea to change the o2 sensor...

Hopefully will get a part number or two out of the conversation.

satanic Grand Master

satanic

Posted
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Posted

Hey tdawg,

I asked my mechanics today and they said that the o2 sensor should not be playing up - they even said the 350kms is quite normal for the car... I seem to think otherwise.

I've had some soot build up since installing the cat back so I might just invest in a new o2 sensor (at least if the new one doesn't make a diff, I'll have a spare one to use).

Thanks

Sumo Mentor

Sumo

Posted
Posted

Best way to check it would be to put an voltmeter on it and look at the feed back you get from it.

If they are replacing them with ford EL ones, I would near say that you could get the specs out of the ford service manual or a Gregory's EFI manual.

I would think that it would take a reference voltage and modify it. I doubt it would be a signal generating one. But, if it is a signal generator you would have to get a oscilloscope. At a edumacated guess, at 3 wires it should be a potentiometer you will have an input 5-12V, an Earth, and an output which should vary - thats the one you want to monitor.

Cheers

Sumo

blind_elk Grand Master

blind_elk

Posted
Posted

Is that your "city cycle" economy. If so, it's unlikely a new O2 sensor will help, because, as has been mentioned too many times on these forums, the O2 sensor really only works under constant throttle (cruise) conditions. Around town, you get very little time on cruise (compared to "highway cycle").

rob82 Mentor

rob82

Posted
Posted

Your O2 sensor operates up to 4000rpm and just below 0 vacumm. Hold the revs above 2500 rpm and check the voltage between ground and the signal voltage you can do this at the sensor or the ECU it dosn't matter as long as there is continunity. What you should see is an oscillating voltage between 0-3 volts I think. I'm pretty sure if you can replace the O2 sensor with an EL sensor the voltage variation will be between 0-3 volts. I know most 02 sensors are 1 volt but I think there where a few fords with 0-3 volt O2 sensors, perhaps someone could elaborate.

satanic Grand Master

satanic

Posted
  • Author
Posted

So the Ford sensor will work on the R34?

Ever since getting the Cat Back installed, I've begun developing quite a bit of soot on the rear bar after every drive. In the other threads, some have said that the new o2 sensor has cleared this out completely...

Someone care to make a suggestion or two? I definitely know that the car is running rich now that the soot is developing. Carbon just ain't burning completely...

disturb3d Community Regular

disturb3d

Posted
Posted
So the Ford sensor will work on the R34?

Ever since getting the Cat Back installed, I've begun developing quite a bit of soot on the rear bar after every drive.  In the other threads, some have said that the new o2 sensor has cleared this out completely...  

Someone care to make a suggestion or two?  I definitely know that the car is running rich now that the soot is developing.  Carbon just ain't burning completely...

Mate,

I get the same problem aswell, so much build up around the boot and bootlid, but my exhaust is from the turbo back. Again it must be a common problem with the r34's must be unburnt fuel.

satanic Grand Master

satanic

Posted
  • Author
Posted

Well regardless of what's the go on the 34 (dead or un-dead), my car just clicked 40k Kms so I'm going to replace the o2 sensor just to be sure. On the other thread it was stated the following effects:

1) Increased Economy

2) No more black soot on rear bar

3) Better performance (not power, just overall engine running)

disturb3d - I'm going to get a 3" front/dump pipe as well as a 3" high flow cat installed soon... I don't want to have black bumpers after each drive - will let you know if the o2 sensor changes anything!

Sumo Mentor

Sumo

Posted
Posted

An O2 sensor will not change the soot being produced at full throttle.

The O2 sensor is only used when the ECU goes into closed loop mode - which is at idle/cruising. The ECU at full throttle looks at the AFM signal and tries it best to make decisions based on that reading. It doesn't try and lean it out till things are nice cruisey, less risk of leaning a motor out and causing damage.

Cheers

Matt

blind_elk Grand Master

blind_elk

Posted
Posted

Try cleaning the injectors - they may have a bit of gum build-up, permitting too much fuel to be injected.

Try going for a "cruise" along the highway - the Central Coast must be nice this time of year.

Sumo Mentor

Sumo

Posted
Posted

Mate, Im not too sure what would produce better fuel economy. If everything is checking out fine I would look at your driving styles, the right foot controls most of your economy.

Blocked injectors I would think you would have worse trouble then bad economy - but it is plausable.

Small things produce better economy as in good quality engine oil, clean air filters, pumped up tires, quality fuel, IAC working properly (your car adjusts idle as it warms up?).

Im not to sure on what kind of memory capability the skyline has, but maybe its worth erasing that by undoing the battery and pushing the brake pedal. Should reset a few values the car "learns" about different throttle and load positions.

Cheers

Sumo

satanic Grand Master

satanic

Posted
  • Author
Posted

Thanks for all your help Sumo...

Looks like i'll be replacing the o2 sensor, running a bottle of injector cleaner through the car, as well as resetting the ECU (properly this time).

Will post up any improvements at a later time! :D

Sumo Mentor

Sumo

Posted
Posted

Is always good to hear on what kind of results people get by trying different things.

I have never really taken notice how many kms I get to my tank in the 33. I always forget to check the trip meter or reset it.. By all means if you can replace the O2 sensor and run an injector cleaner (I used Caltex Techron 5000 to get rid of my nasty injector noise my car got from 5hit fuels we get out here in the country) , If it produces no result, back to the drawing board - but if it does your set :D

Cheers

Matt

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