Jump to content
SAU Community

Recommended Posts

Hey guys, I have a few ideas already but throw some at me.

ATM I'm getting 320ish a tank.

Mods are simple, fmic, boost tee with gauge, running 10pound with 3" catback system

Thinking of doing the 02 sensors first.

Cheers. ~ash

Link to comment
https://www.sau.com.au/forums/topic/400450-low-fuel-economy/
Share on other sites

  • Replies 41
  • Created
  • Last Reply

Top Posters In This Topic

try getting some contact cleaner and cleaning the afm ( if you have one). I had the same problem when i first got my 33 and by changing the sensor and cleaning the afm im getting a lot better fuel economy

how about you tell us how many litres you are classing as a "tank". that will give us a better idea of whether your economy is just ordinary or extremely crap.

also, what sort of driving are you doing (city driving/highway driving) and how do you drive? if you do city driving and boost it often then you will get pretty crap fuel economy and no amount of changing sensors will help much.

Highway driving mostly.. I don't boost like an average wanker, i don't see a need in showing my car off to the 5-0 :P

I haven't tuned her yet, she's due when the money is here, so no management.

300ks to a full tank which is 40lts

ill do the afm and the throttle body when i get the 02 sensor in.

Cheers

40L isn't a full tank.

~13.33L/100ks, is not great, especially for highway driving. It is a skyline though... I get about the same but mostly driving in traffic.

sensors may help but even the minor mods you have done will mess with the factory tune somewhat. You're probably going to need a proper tune

yeah as above, 40L is a long way from a full tank. skylines have a 65L tank. you should have about 10L left when the fuel light comes on.

as for the economy you are getting, yeah that's pretty ordinary economy for highway driving. i'd start with your o2 sensor as that is responsible for altering the mixtures at light throttle. getting a tune won't help too much on highway driving (if the ecu you use still reads from the o2 sensor). you can check whether the o2 sensor is working correctly with a multimeter, or a consult cable.

it's also worth asking what size wheels and tyres you run, as that can make a noticable difference. big rims (17" and above) plus fat tyres will hurt your economy, as will running the tyre pressures too low. engine condition as well as fuel injector condtion will also have an effect. dirty injectors will hurt you economy (and a bottle of injector cleaner won't do squat), as well as a tired engine that is a little bit down on compression will also use more fuel.

If you have low compression that wont be helping, along with a stock computer which is always rich and retarded, maybe timing is out too, plugs maybe old,

a stock dump might be an issue too, i have a 3inch dump you could have $80,

i use to get about 600ks out of a tank with most highway, and that was front mount, exhaust, 10psi standard ecu

now im getting 300 on highway with a whole new setup, gt3040, full exhaust, 18psi, running wolf v500. Kind of depressing as its pretty much the same economy around town...

thats what i was thinking to, but it was the tuners prefered choice of ecu, and i let him know i was more interested in the economy for highway driving and didnt care about around town to much, I was talking to another person with same ecu tuned by the same tuner and they are averaging 550ks to a tank with more power than i am making... I just think its my car, seem to always have problems with something going wrong.

Thought I'd spend the doe and get a compression test done aswell. Booking that in with Pete at rpm.

I'm running 18" wheels with low pros federal/Heros.

I'm thinking it's bc my tank is not 65 ltr as u guys keep saying it is :P. don't ask why, it was like that when I bought her.

Thanks for the replies, several minds are better than 1 so I thought I'd check.

~ash

thats what i was thinking to, but it was the tuners prefered choice of ecu, and i let him know i was more interested in the economy for highway driving and didnt care about around town to much, I was talking to another person with same ecu tuned by the same tuner and they are averaging 550ks to a tank with more power than i am making... I just think its my car, seem to always have problems with something going wrong.

I dont think that tuner is giving you value for money, sounds like a rip off to me. I just found a new tuner and he could not believe the tune that had been done previously, no wonder the car had no top end, they had tuned it to be weak at the top.

taking someone elses tune and putting it in your computer is not a tune, thats what they can do and they know you have no idea. He should of tuned it for more than just highway. must of took half an hour that job.

Edited by SliverS2

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • sold listed as a Tomei LSD 1.5 Way For 1998+ Nissan Skyline ER34 25GT RB25DE w/Open R200 https://www.ebay.com/itm/174006114594?campid=5338967980&mkevt=1&mkcid=1&toolid=10050&customid=&mkrid=711-53200-19255-0&loc_physical_ms=108689&loc_interest_ms=&campid=5338967980&mkevt=1&mkcid=1&toolid=10050&customid=71883f2ccc571356e0a757bc7adfdde2&mkrid=710-53481-19255-0&loc_physical_ms=108689&loc_interest_ms= it went in like butter all gears, alignment, back lash etc, rotation and clearances correct, and if rolling all rotates smooth and free when coasting down road , clutch in or out over 10 mph smooth... its the binding, clunking and jerking from a stop that is most concerning, also seems like its going to tear the tires off in 10 miles of normal road driving. 
    • What 1.5 way? There's no such thing really as a 1.5 way, just different ways of explaining 2 ways with different ramp rates. HOWEVER. In any driving in a straight line your 1.5 or 2 or 1.7 way should have no clunking at all. With the clutch fully depressed the diff should be silent (unless it's welded but I'm assuming it's not). Something aint right here.
    • Clutch is a spec brand, new clutch system,( PP, flywheel, friction disc, etc. pull type) installed 100 miles ago, with no problems.
    • looking for some help and maybe some insight on others experience with a new LSD. R34 GT ran and drove beautifully, but always alot of grip loss due to the open R200 rear end, so I just installed a new 1.5 LSD way into the stock open R200 for a ER34. Simple. Everything seemed right. I test drove for the first time this weekend. as I started to back out the garage the first time slowly with tires straight it sounded and felt like I had a loose or half disconnected drive shaft...that was clucking around loose and shaking entire vehicle, and making it feel like the trans clutch was spontaneously slipping then grabbing very roughly while just letting out pedal slowly. I backed it out went to pull forward with the same noise, shake and slip grab feeling with hesitation, I turned the tires to back out more and then pulled ahead some same thing but worst because of added wheel resistance (which that I expected) puzzled … pulling it back in checking everything over and finding nothing wrong, I tried it the next day. same thing, couldn’t believe how it shook everything again making a terrible noise and making it feel like the trans clutch was slipping and grabbing, but I got it out of garage into the driveway, got it straight, drove forward and then reveres a few times in a straight line everything shaking , causing what felt like clutch slip and grab every time, sounded like right behind front driver tire and I could feel it in the floor board with my feet,... worst right when beginning to let clutch pedal out to engage slightly, shuttering and sounding terrible along the way…I managed to slowly get down the road, babying it the whole way, once I was rolling (out of 1st) seemed to be better and between shifts, then clutch felt closer to normal…not slip/ grab etc., but back down to any stop, straight road or turning, same thing. Made no difference if all tires were straight or if I was turning. All other gauge read out correct. with in 2 miles as planned I reached the empty parking lot and performed the break in procedure that came with lsd, essentially to drive in a figure 8 a bunch.  Did this, binding chattering, and shaking the car the whole way. I drove it back home seemed somewhat normal once I was in straight line and past 10 mph or so, and I know it will “bind” on corners and cause some tires squeal when turning especially from a stop, but when I begin to move it still causes what feels like the trans clutch to slip and jerk badly as well as shaking the entire car, and sounds terrible, that I didn’t expect. I used the fluid they supplied with LSD kit and did the breaking, planning to change fluid as they suggest after breaking, but wondering will it get smoother or less aggressive with use? maybe a 1.5 is just too aggressive for normal road driving?   I have a LSD that I put in my 71 cuda when I restored it, with amazing smooth , quite yet effective results. Different style LSD but that ones a joy to drive. maybe expecting too much from this R200?
    • Join SAU NSW for a flame-grilled feed & flame-spitting cruise! Sunday 17th August 2025 3:30PM Meeting Archies Flame Grille Sylvania Waters 4:45PM Cruise Departure 5:15PM Arrival at Cape Solander Kurnell Meet Location: Archies Flame Grille Final Destination: Cape Solander Kurnell *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
×
×
  • Create New...