Do I Need New O2 Sensors?

[chillicatqld]

Just wondering if anyone can help me here.

Got a VYII SS ute - Mafless tune, filter, 2nd hole MCAI mod, MAF pipe, Pacemaker Tri-Y ceramic headers, full zorst duel 2.5 with highflow cats.
Am getting on average (on paper not instrument readout) approx 16.5-17l/100klms - or 300 klms per 55 litres around town driving - and that is mostly fairly conservative driving (gear changes from about 2000 - 3500 rpm).
Thought may get some better fuel economy when went Mafless - but hasnt changed any!

Mark at PT reckons to change O2 sensors next (as they were lengthened by TaipanXP when changed zorst system) He modified my lean cruise on last look to see if this would help - but it hasnt. He said one of O2 sensors was reading "a little eratic"

Anyone have any thoughts on this - or is 300klm/55 litres about average for round town in this sort of drive??

Thanks in advance for any help/opinions/suggestions....

[pagey]

I had the same problem.. or sales pitch :stick: :D

I replaced mine and do get better fuel economy...

[chillicatqld]

What sort of economy did you get pre change - and what you get now Pagey?

BTW it isnt a HOlden sales pitch - this is from Mark at PowerTorque trying to help me solve the problem?

Cheers for prompt reply

[pagey]

yeah.. Mark @ PT told me the same thing.

I was around 14L/100 highway.. now 10-12 with a little cam.

A dodgy O2 sensor will also restrict the potential to release all your power.. by confusing the PCM with intermittant readings.

Cheers
Pagey.

[alexcs]

will a dodgy o2 sensor usually throw up an engine light or not?

i had extractors done last week and the thread was stripped from factory, they were able to pull it out but the barrel was squashed a little on either side of the sensor, rekcon that sort of damage will translate to internal damage? what sort of breathing room is inside an o2 sensor, the barrel above the thread?

[chillicatqld]

Im getting quiet reasonable figures on highway (around 10's) always have. Drove to Vicco and back before had mafless - and got 11.2l/100klms over 5500klms travalled. It just sucks heaps round town. Think may just have to try it...

[chillicatqld]

hey alex. i never have had an engine light come on! so who knows how correct they are at their measure

[alexcs]

i rekcon you sohuld go back to your tuner, see if theyll thorw on a pair of loan sensors and dyno back to back. or jsut borrow someones 02 sensors and get it dynoed back to back, pref someone who gets excellent fuel econ. just be careful removing them, if they havent been removed since factory, you might have a stripped one. ive heard of this happening quite a bit.

[pagey]

It just sucks heaps round town. Think may just have to try it...


:lol: :lol: Maybe ease up on the right foot.

It certainly nothin out of the norm to be getting round 20L/100 km around town etc... tends to happen when you have 5.7Lt at your feet.

If you are getting near 11 on the highway - I wouldn't be too concerned.

Alex.. A dodgy O2 would not nessessarily cause a warning light.

Regards
Pagey

[alexcs]

yeah hes right, if youre only averaging 30-35km/h in traffic, 16-17 is perfectly fine. if youre averaging 45-50kmh, the it might be considered a little high.

[chillicatqld]

does 300klms for 55 litres sound common to u guys round town then? it doesnt get any better if i drive like a granny!!

[alexcs]

i get about 400km to 60 litres, averaging 40km/h since i got extractors. prior to that it was maybe 400 to 65 litres.

[cutter bob]

does 300klms for 55 litres sound common to u guys round town then? it doesnt get any better if i drive like a granny!!



very common, every tank actually

[chillicatqld]

gee those crew must really drive like grannies that get 13's around town !