Before my car went into the bodyshop I'd get about 280-320(ish) MPG out of a full tank. Techtom would report correct voltage for the O2 sensors and would flick between lean and rich more than five times in 10 seconds as it's supposed to report(at warm, 2000 rpm) but not now!

 

Since the car has returned from LEONARDOS it's guzzling fuel like it's gone out of fashion. Mrs T noticed it first when it managed about 50 miles on a quarter tank. I noticed it yesterday driving down from home to work 280 mile journey. Normally I would make it down and be close to empty, but yesterday I had to stop at Rothersthorpe(about 210 miles covered) and put another 20 squids of Optimax in!!!

 

O2-1 is stuck on lean, O2-2 is stuck on rich!

 

Voltage is OK and within the norm at 0.9volts.

 

Are they Phuket???

 

I think they are!

 

Just thought I'd share that with you boys and girls.

 

 

 

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o2s - could have gone pear shaped - are were they disconnect if so are were they reconnected properly - Check the service manual and do a O2 diagnostic (same page as ECU diags) and that will tell you what for sure if they are fucked !

 

thought i would get that one out before someone plays the Self learn mode on the ECU card lol

 

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Z ya

 

Nico91TT

 

 

God is coming ...and he dont have stock turbos . . .

Cheers Nick, I'll have a look but I've done 86K now and I was under the impression that they only last about 80K maximum so should be changed anyway.

 

Can't see any reason for them being disconnected, Techtom is picking up a voltage for both sides and a lean/rich reading.

 

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[This message has been edited by Timmy_Turbo (edited 09-07-2002).]

Right hand bank has an air leak pushing it rich, the left hand bank doesn't have an air leak - the ecu reads the right O2 and leans out the mixture - left bank runs lean, right bank still runs rich cos of air leak

 

HTH,

 

CheerZ,

 

Andy

I bow to the superior A level interlect of the Muffman LOL

 

 

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Z ya

 

Nico91TT

 

 

God is coming ...and he dont have stock turbos . . .

Cheers Andy/Nick, never ending is it?

 

 

 

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Right peeps.

 

Is this my troblem too. Last time I did a big run in my car I only got about 260 miles to a tank, and 90 of this was at 60-70 mph.

I think I am running lean because of the soot that comes out of my exhaust.

 

How can I check my O2 sensors?

 

Staurt

Presumably you mean you're running rich ...

 

There is a documented O2 test along with the ECU diag. Although it does indicate whether they're working, it doesn't really tell you how well they're working. You'll need a Consult/ConZult/Techtom for more detail.

I suspect I might have a similar problem. Where should I start looking for the leak

Have a shufti here :- www.z-car.net

 

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Z32 technical article index

andy ive had my 02's replaced and i still get about 200 miles to a full tank.any ideas?

ive never done 300 miles to a tank ever!i can wish

Get a Consult/Techtom on the car to see what (it thinks) it's doing.

In case my crippling sarcasm threw some of you guys Andy DuffTT did infact have a very valid point as always.

 

Still worth doing the O2 diags first tho before you rip the facia off to check for leaks there.

 

Timmy i would check for Air leaks around the IC's where the Facia has been replaced !

 

 

 

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Z ya

 

Nico91TT

 

 

God is coming ...and he dont have stock turbos . . .

cheers andy

Timmy,

 

The simple way to test this is to swap the sensors with another set (or else swap one side to the other as it's unlikely they're both knackered). If the Techtom readings change when you do either of these then the problem is most likely the sensors.

 

If the problems on the Techtom don't change then a leak seems most likely. I was struggling to think how the bodywork could cause this but Nico's idea makes perfect sense. I hate people who are always right but remember that he did have 2 years of twiddling his thumbs to think about stuff like this.

 

Changing them is a bugger of a job though. If you're down at SE, they've got it down to a fine art and managed to swap mine in about 10 minutes. They also did me an extremely good deal on a second hand one - which I'm sure they'd do for you too as they do look after their loyal customers

 

Buying them new they're in the region of £80 each from Nissan UK.

 

Good luck

 

Dave

 

[This message has been edited by Hairsy (edited 10-07-2002).]

Now, this might seem like a simplistic view (and No Timmy, I'm not taking the piss!) could it possibly be that it's not the O2 sensors causing the problem?

 

You mentioned that the car was okay prior to the 'body mods' and only now is returning poor fuel consumption.

 

Could it be that, perhaps, the new add ons are actually not helping the aerodynamics of the car?

 

What sort of mileage does Mac get out of his? I can expect 50 miles on quarter of a tank on mine, but I do a lot of short journeys.

 

Just my 2 penneth.

 

Tim