Ok im taking a leaf out of Bains book. My fuel economy is a lil weird atm. Basically i can fill up till its overflowing, drive smoothly, yet apart from a long distance trip i just did, ill only get maybe 300-350km out of a tank. Its not normal, or so i think. Can anybody tell me how fuel goes for them?? Thanx heaps guys!

hopefullt your car isnt running badly rich after your new exhaust. it shouldn't.

when was the last time the car had a major service (lead, plus, rotor, cap, etc) cos i found after mine there was a huge improvement brought it down from 13ish to 11l/100k
another thing i had done a while ago was the injectors taken out and cleaned that made a difference too

is yours efi or carby tho?

i have a efi TP.. 62?? Litre tank and i was getting around i think 300+km. After doing a air filter and efi clean it jump back to 450+km, that’s hi-way driving and town driving, about half for each, i never really use aircon unless it is a hot day.. and i believe i will get better economy after i tune the car up more change spark plugs and leads (its been 20, 000+km since they have been done, just need them money first)...

btw i just sprayed carby cleaner into the throttle body cbt taking out the injectors and cleaning them.. and I do have a lead foot :P


hope that helps.

what is the size of that tank
who is good at math

10lt/100km = # 40 litr tank =400 km ok 62 lt tank =620 km is that right ?
11l/100k =?
13lt/100k =?
15lt/100k =?
20 lt/100km =eek! might as well hire a taxi !
64l im fairly sure on the sedans

so your right 10/100km is 640km

i normal had 550km per tank so 64/550*100=11.63L/100km

when you think about it, that formular is wrong because normally you dont use the FULL 64L

i know this is kinda of topic but it found a more accurate way of working out how many L/100km you car gets

full your car right up to the brim, then drive too 100km as much as you can and fill up again to the brim and take note how many litres it took, simple :)

usually 55 litres will get me 450km of mixed city/highway driving, with the odd burst from the traffic lights. which by my calculations means im getting around 12L per 100km

thats with a weber carby, 5 speed manual usually changing at 3000-3500rpm.

have you done any intake mods ? if youve upset the MAF by taking out the air filter and using a pod on the end you could be getting a very rich mixture and poor performance.

Well all ive done is an exhaust system and CAI. Like i said on long trips its fine, but other times, its horrible. I drive to uni from home 4 days a week. Its about 50km one way, and i have to fill up on the way back wednesday, if i fill up 100% monday on the way. I drive pretty smoothly, yet the fuel just dissappears! Yet the funny thing is if i drive hard, its almost as economical. The thing that also really gets me is if i give it a lil bit of stick, like rev it a bit, but not go full-on it takes more petrol then any other time..........:nuts:

i actually noticed that as well, on a moutnain run i filled up after and it was pretty horrendous at about 16-17L/100km. But if i really (i mean go really) slow i can get it to 12L/100km, but most of the time never going above 2200rpm is just ridiculous. so thats not possible, so usually give it a bit sometimes, and it ends up 14-15L/100km. Thats pretty expesnive. So one trip to uni costs 12 bux at a 1.30 - based on 15L/100km and 60km round trip! Really depends on my foot i think, injector clean was good but a while on it seems to be back around the same again.

(note auto chews more fuel)

Hey there all just wondering if theres any way to drop my fuel eco down a lil im on about 14ltr/100 im getin about 380 outa me 64ltr tank so i think its around that mark not to sure.
any sudgestions would be appreciaited. me car is a 89 TN carby version

i think you guys are either booting it to much. or for the carby guys, the carby is a bit stuffed and not working efficently. id recommend a weber conversion (do a search). also when driving try and keep the accelerator in a stationary position where practical. constant movement of the accelerator pedal means squirts of fuel keep getting pumped into the carby. this is not good for fuel economy. also try and save momentum, if your approaching a red light and there is room, brake early to slow the car down a fair bit and coast up to the light, hopefully when it changes you will still be doing say, 30-40km/h and can save the engine a lot of work.

also i wouldnt bother making your own cold air intake, it comes stock standard with its own one anyway, if you have a tm it goes over the rocker cover and gets a bit hot maybe try heat proofing it a little better. go to a good auto parts store and get a replacement K&N air filter for your standard magna air box it will be in the range of 80-110 bucks. make sure you give them the exact year and mdel of your car.


also its worth considering going to an exhaust shop and replaceing the restrictive standard mufflers itll free up some power and give a nice exhaust note. tell them what your after and what they recommend.

The last time I filled up I got 13L/100km. Keep in mind that was all city driving and I was booting it hard off the traffic lights every time!

I haven't done highway driving since I put on a Vortex muffler (from the Queensland company), except for the other day when I drove 300km on a trip through the Adelaide Hills. My fuel gauge reads lower than it should (only goes to 3/4 when full, I usually go my how far I've gone), and its just under half full (not that I trust it).

Anyway if I go on a steady highway drive at 110 (I'm not saying 120 like most people drive because that'd be dobbing myself in)! lol , I get around 9.6L/100km (thats before the muffler). I'd love to see what I'd get now on the same drive.

When I was up in NT on the open speed limit roads before I got my new muffler, I drove along at 150km/hr and still got around 13.5L/100km

My fuel gage is the same full is only 3/4 on the gauge. Is this just a TN thing or is it just rare occurance.

Mines a TP EFI, but I guess it still uses the same gauge I guess. Those figures I gave was with a manual by the way!

There's three things that can go wrong with the fuel gauge. The first thing is the voltage regulator, the second the fuel sender unit and the third the fuel gauge.

To replace the fuel gauge the dash needs to be taken out, and it may cost around $150, so its not really worth it especially if it still acts as a guide! You'd be mad to trust a fuel gauge on any car thats that old anyway! :) lol

You'd be mad to trust a fuel gauge on any car thats that old anyway! :) lol

Yeah but what else can u go by??? i dont always 100% fill up, so i HAVE to assume its right.

Yeah but what else can u go by??? i dont always 100% fill up, so i HAVE to assume its right.

Thats very true! Um, take note of the mileage you have done?

Like fill it up, reset the trip meter. Then if you travel 400 km and only put 20L in, then you don't reset the trip meter. You think like, 400km down with an 82L (the fuel tank is 62L right) capacity. If you travel another 200km, and put in 40L, you think 600km, 122L capacity. Etc, and then the next time you fill up top it right up and start again. OK sounds complicated, but it saves spending money on the fuel gauge when the regulator and sender unit is probably going to be reading inaccurate anyway. Fuel gauge, sender and regulator = a lot of money and the regulator and fuel gauge are unreliable parts on these magnas anyway!

My fuel gage is the same full is only 3/4 on the gauge. Is this just a TN thing or is it just rare occurance.


my fuel gage is the same, only gets to 3/4 full but has been on full once or twice :nuts:

TP EFI with the mods in the sig i do 320kms a week from full every week it uses 32 ltrs driven hard, if your getting crappy fuel econ try a new airfilter and reset the ecu if efi, if it still doesnt help mabe the o2 sensor is shagged and your running in default map or failsafe mode, bottle of fuel injector cleaner wont hurt either

PeteW

Thats what I was gonna say, o2 sensor if EFi. My old R31 went from 600ks to 350ks on the highway, just from the o2 sensor, now its fixed and i'm told its better than that.

UPDATE time. Well the past 3 tanks ive filled up FULL, and im gettin bout 400km before the fuel light comes on, im guessin that sounds about right. So other 1st Genners tell me what your gettin. Also how many kms can i get once the fuel light comes on before the tank runs dry?

Do all Tp's have fuel lights? I've never seen mine! I'm pushing 470km out of this tank and its starting to get to the stage where I think maybe I should fuel up (because of that fuel gauge is faulty). It still kinda ready about 1/5, but I don't trust it. About 280km of that was highway driving though.

Oh and PeteW, if your TP is using 32 litres for 320km driven hard you must have done something right with the modding! Thats exceptional. These are thirsty motors and stock settings supposedly they use to run 10L/100km driven like a grandma on the highway. What mod do you reckon you did that can account for this?

Do all Tp's have fuel lights? I've never seen mine! I'm pushing 470km out of this tank and its starting to get to the stage where I think maybe I should fuel up (because of that fuel gauge is faulty). It still kinda ready about 1/5, but I don't trust it. About 280km of that was highway driving though.



My 1989 TP Ex has a Fuel light but we it came on i only had like 500m to get fuel :doubt:

and i think all the fuel gages are all broken. mine wont go passed 3/4 but it is fine when it is 3/4 and less :nuts:

Yeah 3/4 when full! Obviously no point getting it fixed since its an inherent problem with them :(

update on this, i've been driving very moderalty over the past month, with the auto ive managed consistent 12.5L/100km. No booting at all! With the way petrol is there will be no thrashing for me lol

Also for me it would not justify trying to get better economy, the cost in the process for the llittle gain and amount of km i do woudlnt be worth it. Unless someone has a cheap fix....

I take it you have a TN/TP? Maybe adding a homemade CAI would help? Basically just take the battery out, replace the stupid air intake thing with flexible but study plastic tubing and run it down next to the radiator (there a narrow gap there) and add on a homemade long sleeve to fit in the gap. Then heatshield the whole intake. The airbox and the inlet tube get a lot of heat from the engine, and the radiator hoses get close to the filter box as well. If you get two of those cheap dashboard protectors from supacheap, they have foil on one side and a foam like stuff on the other side, that will easily cover all the intake pipes, surround the airbox, and also the CAI you put in, as well as some left over. Put the foil side up, it doesn't get warm and I know that it won't really reflect the heat, its just better this way as you have a nice shiny air intake, filter, and CAI tubing!! The other side would look pretty crappy after getting grime on it too, the foil side is easily cleaned. I'm using the cheap but effective grey electrical tape (you know the wide stuff thats got a pretty good stick). I've done about half of that so far, haven't had time to do the whole thing, and I ran out of tape :( (no I didn't tape the whole thing, enough to hold the shielding firmly in place, suggest you start with more left on the roll!). The filter box as everybody knows on the TP is a stupid design, you have to take the battery out and undo the 3 bolts and take the filter box out to clean the filter, well you might as well clean it whilst you're there as you need to take it out to install the CAI.

Don't know how effective the shielding will, I haven't done any driving since doing it, only started last night. Should be quite reasonable on the highway though!

And that setup is cheap! You can make the funnel thing out of an old icecream container! (i've seen this done, I would have thought it had melted but it didn't)

Good thing about that CAI is that surely the heatshielding etc. would help, and its easy and very cost effective. Even if the benefit is slight, you spent like 15 dollars or something so no complaints (I overestimated that price)

My fuel effiency seems to be going down every week, or is it just the price going UP?