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howie/shoebox - those fuel consumption figures you both getting are quite high even for the mods given especially shoebox's since you got afc to adjust your air/fuel.

You'll find most of the 34 guys are getting between 13-14.5 litres. I was a bit worried at first, so i started a thread about it, and it looks like 90% of the 34 guys on this site are around this figure.

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i figured the O2 sensor was in the AFM you still didnt anwser my question how much !?!?!

Need to know what you were talking about first mate.

Anyway the O2 sensor goes into your exhaust, just after the turbo on the dump & by measureing how much oxygen (ie O2) is in the exhaust gas it can determine if it is running rich/lean or ok. Over time they wear out & usually read less voltage meaning it thinks the gas is lean therefore the ECU enrichens the mixture to compensate.

Anyhow to answer your question, you shouldn't be looking at any more than about $120 (I'm not sure I got mine for special discount, old work friend :laugh: ) Even with that price though it will pay for itself within about 3 months & then you'll end up miles in front after a year.

Need to know what you were talking about first mate.

Anyway the O2 sensor goes into your exhaust, just after the turbo on the dump & by measureing how much oxygen (ie O2) is in the exhaust gas it can determine if it is running rich/lean or ok. Over time they wear out & usually read less voltage meaning it thinks the gas is lean therefore the ECU enrichens the mixture to compensate.

Anyhow to answer your question, you shouldn't be looking at any more than about $120 (I'm not sure I got mine for special discount, old work friend :laugh: ) Even with that price though it will pay for itself within about 3 months & then you'll end up miles in front after a year.

ah yes the O2 sensor i am now on the same page thanks to your lovely description cheers

So can anyone get a new O2 sensor for me for a good price? I get around 16.5-17l/100km :( .... but I do sit idling for 10 minute periods many times a day writing up notes with the a/c on (which is the big reason I am getting a new radiator shortly) .... still that shouldn't affect it that much!

$99 is deacent for retail, though it doesn't hurt to shop around. Maybe I could set up a small group buy with my old work mates if there were enough people interested, though I don't know how much cheaper u'd get it than that.

Edited by JazzaR33

thanks Luke - I should get one very soon to hopefully fix my fuel usage issues.

I take it you just ask for an RB O2 sensor?

Do they have a specific thread type or anything? I would imagine that R33 and R34s are the same?

Yep a group buy would be good Jared, but unless it was going to be a fair bit cheaper than $99 I wouldn't bother if I was you.

Make sure you specify model too, it may be different from 1 engine to another depending on series & model. I wouldn't be surprised if it's the same as an R33's but you have to make sure.

I think if there was enough interested with a group buy I could get them about $15 cheaper. Don't know if thats enough to sway people though.

even if it isnt... brand new parts dont hurt at all. they will cancel out any doubts u had about the source of problems.

Yes.. My problem some time ago wasn't the o2.. I replaced mine even though it appeared to be swinging within spec.

So out came the injectors in went the new and fuel consumption went from 350km's per tank back to its usual 450 to high 400's.

Andrew, I'd have the tune looked at first to be sure it is an oxy sensor that's causing your fuel use issues.

Although I guess in the realm of you and cars, a hundred bucks is about the cheapest thing you'll ever do!

The fuel consumption that Andrew is getting pretty is very high , I'd say replace the O2 first & then see if it fixes it, if not keep the old 1 as a spare. The more kays and the more hard driving it's suffered the more likely it's stuffed. Mine was screwed even with less than 50,000 on the dial & it probably should have been changed about 5,000 earlier as it was already chewing an extra litre per 100 to what it should have been.

Yes.. My problem some time ago wasn't the o2.. I replaced mine even though it appeared to be swinging within spec.

So out came the injectors in went the new and fuel consumption went from 350km's per tank back to its usual 450 to high 400's.

Common with older type injectors for this to happen, usually the spray pattern starts going a bit crappy & stops vapourising properly, instead you get almost a solid jet of fuel. Sometimes they would also not shut properly so would be flowing fuel all the time, but this was less common. Dual fuel cars are the worst, the crap building up from backfiring & oils mixed in with the gas collecting on them makes them stuff up eventually guranteed.

Cleaning usually fixed the problem, though if you wanted to go higher flowing injectors it was still better to put the money towards that.

Edited by JazzaR33

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