I know I know Fuel consumption again

[srb 33]

Ok,

I have reset my computer.

I have done a diagnostic check>>code 55 (engine light flashed 5 x slow, five times quick)

I filled tank full with optimax.

I drove like a granny for half tank (160 aprox km).

I had Sat where I did some racing, (my mate got rx7 series 5 running with 10psi boost and I got him off the line but then that rotary just roars coming from second onto third) anyway back to the point.

I then drove agian like a stiff in a straight jacket, and took it easy.

All up I got 330km driving conservatively for majority of the time (mainly city driving). I have read posts where guys get 400km hooning around, and 450 to 500 km driving like stiff.

Mechanic is pissing me off because he checked the read out from exhaust and it is perfect. So he believes it is evaporation problem, this is why I took my R33 back to have the neck on petrol nozzle replaced. (didnt cost me a cent)

Then a lot of you guys here are undecided whether it is O2 sensor or not.

Another option is to take it for a Dyno tune, but my mate reckons it's a waste unless I have some modification done.

Mechanic has told me to fill tank again and drive like a stiff again, then call him with the result. I really cant be fU**ed driving like a granny again.

I have gone through previous posts on this topic and it is undecided what the possible solution is. If you guys get 400km hooning then I want that too.

Where to start?

[Spook's_Skyline]

do the extra 50/75ks a tank matter?

i genereally get between 300-350 a tank, normal driving and im happy with that

never less than 300, but if i do some highway running, it gets better

[CroatianDlite]

it does matter dude - when petrol is above a dollar ten a litre!

i feel your pain.

after O2 sensor change - i know get about 300 - 320 a tank... but usual driving means i must change gears by 4K rpm, and half a tank is highway driving... hmmmm

i sometimes get a strong smell of raw fuel when the car starts up (hot or cold) and sometimes when i come to a complete stop from a fast speed.

i always thought there was a problem with the fuel intake neck and that cuaz its freakin loose...

a friend seems to think that i have a frayed pipe somewhere that is letting out vapours - but i dont know if its enough to cuaz a lot of furel wastage... hmmm

so yeah to all the guys that can solve this - please help us out!

[DRFT33]

i got the same problem. get about 300km on a full tank. haven't bothered to check it out just yet... but will be soon when my wallet goes empty.

[Spook's_Skyline]

if u are worried about 50ks a tank difference, probably shouldnt have bought a skyline . . .

mirages are very thrifty with their fuel usage

edit: should have added above that i never use optimax as it seems to return less milage

i only ever use the BP goodstuff, car seems happier running it

[wilch]

I use to get about 250 to a tank. Now I get around 320-350 to a tank with some spirited driving. I'm happy with that.

Fuel usage should drop down once I get a powerfc and lean everything out though.

ps.. i thought 320-350km's with a slightly modified skyline was the norm

[Jimbo2000]

all cars get different milage.

it depends on tune as well, i have some power and still get 400k's

turbo cars use a lot of petrol, seriously if you cant afford petrol get a smartcar

[DRFT33]

if 300km is the norm then thats ok. i just thought that there may have been a problem. i was just being sarcastic about the petrol... i'm not that pov

[jager]

yeah know what ya mean still tryin to find my prob out since i got the car i struggle to get 300ks to a tank killin it its like 150. pushing now and then it's like 220 most times i get 250, i have replaced the end tank cap like 3 times new rubbers but i still get fuel coming out da side of the car, getting a new fuel pump GTR, few other mods so it'll be checked over again by tsomeone else

[srb 33]

It's good to see that others share the same prob. The price of fuel doesn't worry me, I know driving a performance car =more fuel. However I didn't buy a v8 because I didn't want extreme fuel consumption, so I got a skyline. I dont drive to work, I live near by, so $80 a week and no trips up the coast equals a bit too much, especially when R33 run at 12litres per 100km so add a few mods, exhaust system and maybe more boost and you'd expect it to go up a few litres maybe 15 or 16.

Anyway good luck to whoever works it out and share your knowledge. I should be working not messaging at Skyline forum. Bye

[vape]

Hi All,

I have been reading about this issue for ages before I purchased my Line. I got a 97 series 2 gtst manual. I use nothing but BP Ultimate after reading the thread on why optimax was not good. Anyway, I have no mods. Just a different exhaust for compliance when she was brought into the country.

I am getting roughly 480-560 off a tank. I only ever run till the light comes on - so I usually fill up just under 60litres. If I drive like I have a speed addiction (who doesn't...) I get just under 500kms.

I don't understand why you guys get such poor distance???

Happy to try and list differences between my car and yours to see where the issues may be?

Rob

[locosam]

I get just a tad over 350km just when the needle is above the last marking (no fuel lights yet), i guesstimate i could just hit 400km if i really push it (this is also after i fill the tank right up to the brim).

I thought this was pretty normal, but the thing is, my car is stock (just out of compliance with no mods), plus i travel on highways for about half the kms i do...So really my car doesnt have very good fuel consumption

[CroatianDlite]

the problem is that many of us are getting a huge difference in fuel consumption... we arent talking 50 km - we are talking 200 - 300km difference in range... for some people, thats double of what they experience.

there has to be a logical explanation. esp if the car is close to stock

all i have is exhaust, and 18" rims (245/40). everything else is stock - now i should be the one getting close to 450 or 500 km from a tank - not someone that has done minor mods! hahaha

i have been driving for 2 years with my line knowing that every 225km i have to start searching for (back then optimax) fuel.

now i replaced o2 sensor and i have about approx 75 km to each tank. still not good enough in my liking

if everyone was experiencing only 300 kms with their lines - of course i wouldnt be annoyed - but i am becuase i know the motor is capable of doing a lot better.

so yeah - thats why some of us are pissed off from my point of view.

[Jimbo2000]

as i said it might be all about the tune

i got a lot of mods (bigger turbo,injectors,pump ecu etc etc)

and get 400...

before throwing the PFC in i was getting 250 k's per tank (runnnig a really bad tune and managment)

so yeah if i can get 400 out of 220+ rwkw i cant understand why stock or close to stock cars are getting average 300

[CerealKiller]

Hi All,

I have been reading about this issue for ages before I purchased my Line.  I got a 97 series 2 gtst manual.  I use nothing but BP Ultimate after reading the thread on why optimax was not good.  Anyway,  I have no mods.  Just a different exhaust for compliance when she was brought into the country.

I am getting roughly 480-560 off a tank.  I only ever run till the light comes on - so I usually fill up just under 60litres.  If I drive like I have a speed addiction (who doesn't...) I get just under 500kms.

I don't understand why you guys get such poor distance???

Happy to try and list differences between my car and yours to see where the issues may be?

Rob

I envy your fuel consumption! I get about 350 when the light comes on. 400's my best with a lot of highway driving. I don't drive hard (shift before 4 grand). My only mods are exhaust, front mount, pod, fuel pump. I run at 11.5psi (0.8bar). I'm currently searching for a Z32 O2 sensor. Hopefully that will help me get to 400 daily driving...I'll be very happy with that.

[CroatianDlite]

just quickly... for people (with stock fuel pump and tank etc) who wait until the light is on to refil - it isnt good cuaz ur fuel pump is workin its nuts off and is overheating. u need to keep the tank at least a quarter full...

anyways - thats what a number of mechanics have told me for EFI cars.

yeah jimbo u see where im coming from! haha

[PTR33]

OK, let's compare apples with apples here.

How many litres are you putting in when you fill up after using "a tank" 40? 50? 60?

I get about 11L/100km during the week driving to work (mainly motorway) and 15L/100km on the weekend mainly round town and more spirited driving.

Litres per 100km is an official fuel consumption unit of measure. Smaller is better.

It's easy to work out

• fill tank
  
• zero trip meter or note odometer reading
  
• drive car until down below 1/4 mark on fuel guage (or whatever)
  
• fill tank and take note of litres of fuel added and kms travelled
  
• use formula L/100km = Litres multiplied by 100 and then divided by kms
  

example, my fill up last night was 41.16L for 368km

41.16 x 100 / 368 = 4116 / 368 = 11.18 L/100km

on the weekend I might use 45L to do 300km which is 4500/300 = 15L/100km

you can also do this over several fill ups by adding the fuel quantities together and noting the total distance travelled. All you have to make sure is that uou start and finish the "test" with a full tank to get an accurate fuel figure.

At least if you use this method you can keep a check on trends in your own consumption and also make valid comparisons to other people's fuel consumption.

If you have a "device" that can display injector duty cycle, e.g. AVCR, consult port scanner, or any of the other gizmos that can do it, take a look at how much difference there is between just cruising with the flow in traffic and jerking back and forth in a zoom/brake style of driving. cruising at 100km/h my duty cycle sits at about 6-7%.

If I lean on the loud pedal enough to just get into boost it can go up to 25-30%. Four times as much fuel going into the engine for what? just to ease up to 110km/h to gently overtake another car in the left lane?

Huge improvements are there for the asking if you drive like a granny with an egg under her foot during the week, to and from work.

Saving your precious BP ultimate for WEEKEND THRASHING.

Give it a go guys, try posting in Litres/100 Kilometers rather than km/tank.

P.S.

If you are getting 300km/tank and only putting in 40L it aint that bad!

[srb 33]

I like your explanation, but I envy your consumption, if I got driving like a granny what you get on a thrash weekend I could be rapt, 15lt per 100 on weekend is what I am aiming for normal driving.

At the moment I get 17.7 per 100km, thats since I reset comp and started to drive more careful and not pihhhchhhhewwww all the time.

Fiiled 23lt got 123km

then 57lt (click click) and got 330.

23 +57=80litres.

123k +330k=453 km

453/80=5.66

100/5.66= 17.8lt per 100km.

Thats the problem, and I am running on standard boost, I will increase it when I solve this consumption dilema.

[MM2death]

Highway driving i get about 10L/100km

City driving with a stab of the pedal here and there i get about 13.3L/100km

I think it's in the tune as well, just as long as your oxygen sensor is ok etc.

I have a 'few' mods as well.

Scott

[srb 33]

I think there would be a huge difference between an R32 and R33 in fuel consumption, one is a four cylinder the other a six.