[ady9]

so curious as to how much my shit box drinks so i tested it out. just usual driving with occasional squirt here and there

tank 1. full tank got me about 370 ish kms
tank 2. full tank 430-460 ish kms
tank 3. 3/4 of a tank 251 kms

been using bp ultimate and filling up at the same place. anybody know what the hell is wrong with my car? it cant be that shit house on fuel.

ive got an alpina flash - im assuming this may affect how much fuel it drinks to an extent and just the usual mods. jb4 on map 2

this happening to any of you guys ??

[lemonpark]

my avg km per tank has gone up to 20+L/100km and now its around 16L/100km. thats with me flooring the crap out of it every chance I get (map5 with E85) haha. I think after changing my O2 sensors my fuel comsumption has gone down significantly. used to avg 18-20L/100km with the old O2 sensors now its lower and I floor it more often

[naynay]

turn your jb4 off and try again with half a tank. if its still the same then turn it back on. it could be your o2 sensors or try to clean your mass air sensor

[Mayuri Krab]

What is your L/100km figure?

My car sits ~10L/100km, but 90% of my trips are all freeway/high way based with very little traffic.

[donR]

We also get really bad fuel economy 18l per 100kms and that is stock standard and just putting around on short trips up to 50km/h. I notice once I start cruising on longer trips the fuel economy improves.

I assumed it was just all the short trips we are doing

Nevertheless there must be some serious efficiency problems with this engine on short driving as my other car which is twin turbo 2.8l V6 and our old Saab 2.8l V6 turbo didn't use anywhere near as much with the same sort of driving.

So if the O2 sensor is faulty wouldn't that throw a code? Is it difficult to switch?

[Scotty89]

I just did a trip from Melbourne to Adelaide on Friday and averaged 8.3L/100km.

Full bolt on, running map 5 on JB4 with Shell 98.

Only time I get crap mileage is when I mix in some E85 unicorn juice, but it sure is worth the crap mileage.

[Testercles]

Around Adelaide I get around 11 L/100Km. That's driving relatively normal with the occasional spurt upto the limit.
On the highway to and from Broken Hill I typically get around 8.5 L/100Km.
That's being completely stock running Caltex 98.

[Brule]

I average 12L-13L/100km around town with PTF tune and RB's

[Socket]

Same im running JB4 no other mods
ave 10 - 11 L/100 Kms

[naynay]

lol here you go.

http://www.aa1car.com/library/poor_fuel_economy.htm

[naynay]

most likely the first one

[lemonpark]

yeah man I reckon your O2 sensors. like I said mine went down quite a bit after, same thing with my friends S15

[ady9]

it goes as low as 10L and as high as 17L, once i change my map settings from 1 to 2 or 2 to 1 it starts going down, otherwise it says constant at whatever it is - which i thought was a bit strange. ive got catless dps so i do get a code but its normal once going to catless. ill try turning the jb4 off and cleaning the sensor and see how we go. otherwise it looks like new 02 sensors

[Socket]

Hope that sorts it out for you Ady

[Brule]

You can try and clean the maf sensor on your charge pipe,theres another sensor on your intake manifold you can try those 1st. Only use maf cleaner!

It will probably take half a day to replace all 02 sensors. and cost about 500+ if you DYI

17L is crazy

[naynay]

boost leak?

[s2kadrenalin]

Mine hovers around 11-12.5.

[Mayuri Krab]

I noticed my average consumption went up by ~1-1.5L/100km once I went (almost) FBO vs stock.

[donR]

I am thinking we must have the sluggish O2 sensor problem as our car is stock and fuel usage is constantly poor, although does improve on freeway driving but hardly do that.

Just wondering how difficult the DIY is and whether or not it is worth any other mod while one is down that way?

thanks

Don