Fuel consumption

[nick mann]

VR4, eh? Check out www.clubvr4.com as that's the place to be with that car. You won't get 300 miles with the turbos. 200 if you drive nicely.

[Ken2]

Thanks. I checked them out and registered for their forums.

I went for a thrash today, got 190 miles (just over 300km) out of 30L of gas... I was pretty stoked. thats better mileage than my 1.8 GDI.

was probably 1/2 highway driving, 1/2 high rpm thashing.

[Hoppy]

OK, I was seriously thinking of buying a 1.8 GDi (2WD) wagon, based on the fact that a friend got about 400km on less than 1/2 a tank (64l tank I think)... All the car dealers claim how economical they are - an 800km trip was claimed on one tank before the fuel light came on...

So I was thinking lets list up what people get... To be beneficial I suggest the format below to allow easy comparison.

Your Country
Year
Engine variant (eg 1.8 GDi, 2.0 6 cyl 2.4 turbo)
Transmission - man or tippy
2WD or 4WD
Fuel used (eg 91/96/98)
Approx km/tank
Approx volume per fill
Calculated economy (either l/100km or km/l or mpg)

Anything elso you think might clarify - eg modifications, your driving style etc etc

It'll be interesting to see what the norm is...

[ceroc]

Hi Guys

I too have a Lengnum 1.8 gdi gas guzzler, but found if driven manually it dont eat as much. Have found a web page of stockists of 98 octane in NZ http://www.palmy.net.nz/mr2dog/guides/petrol.html

[grolschie]

Hi there.

Your Country: New Zealand
Year: 1997
Engine variant: 1.8 GDi
Transmission: Tiptronic
2WD/4WD: 4WD
Fuel used: 96 octane
Approx km/tank: avg 350 town / 450 country
Tires: 215x45x75r
Intake: Standard
Exhaust: Standard
Mods: Catalytic converter removed after 122,000kms (no real difference except breaths a little easier)


I also have the Legnum 1.8 GDI. Doing long trips I calculated that fuel consumption would vary from 10ishL/100KM through to 13ishL/100KM. No rhyme nor reason why the variation except perhaps petrol age and brand.

My car was missing like it was running out of gas. I put foot down, and car would splutter. Take foot off the gas and would run nice. Problem disappeared after a few minutes and had no problems until months later when it did it again. Went away again, and finally happened again but real bad. I only just made it to the garage without it konking out. Could only press microscopically on the gas pedal, barely moving, without it spluttering and stalling.

Turned out that the high-pressure fuel pump was screwed. $2000!!!! I am so glad I bought a 3 year warranty, as the excess was a mere $75!

Car still CHEWS the gas. I get about 350km's per tank around town. Going up hills or towing, this car cannot do. Very little difference in acceleration occurs from when foot is 1/4 pressed through to fully pressed. I wonder if driving with wooden block under the pedal would make it cheaper to run, seeing it makes no difference in power nailing the gas pedal.

Oh yeah, it runs far better when no passengers, and on cold nights.

[Hoppy]

Hey Grolscchie

10l/100km wouldn't be too bad for a 4WD atuo wagon (I had a T4 Primera auto - it could suck down a nasty 15l/100km when pushed hard, the best I ever got was 8l/100km.

If you know someone with a timing light (or better still a mechanic friend who would swap 1/2 hour of their time for a dozen beers) you should check you ignition timing. Not too sure what it should be on the legnum, many cars have a specification on a sticker on the bonnet (look at underside when you have bonnet up).

Often cars are "de-tuned" (ignition timing retarded) when imported from Japan to NZ so that they can run on 91 without pinking. My opinion is you are better off running 96 and getting better performance and mileage (not to mention reduced risk of engine damage). That outweighs the extra 5c/l in my experiences.

BTW the fuel pump problem seems to be a common one.

Your comment about cold nights suggests that it might be worth making some mods to get more cold air to your intake...

[grolschie]

Hi Hoppy.

Thanks for the reply. Car has warranty with Donnithornes here in Chch, hence the replacement fuel pump (phew!!!), so no mods allowed until it expires, else it's voided.

Next service, I will get them to check plugs, o2 sensor and timing. I never use 91 octane, except for this NZ new '94 Galant SEI 2.0 SOHC I just bought today. It said 91 Octane inside the petrol flap, so filled it with 91. I wonder if 96 would be better though.

I was told to buy AvGas from near the speedway in a petrol can and put 4L of it in per tank full in the Legnum. Apparently AvGas is the goods, and even such a small amount does a great difference. Only, the exhaust smell is a giveaway. ;-)

[wlc21]

Hey Grolschie,

The symptoms your car are showing, are almost identical to what I'm facing with mine at the moment aye ><

You were precisely correct about power nailing the accelerator - absolutely useless. Worse of all, when the accelerator is fully pressed, which the car reluctantly reacts to it a few seconds later, it makes this
unhealthy 'croaking' sound at the the rear of the car, it sounded as if the muff was about to fall off. (But still unsure exactly where the croaking is from unfortunately)

Anyone else suffers the same problem as I do? Car was jacked up and nothing seemed to have loosen'd. *bangs head on the wall*

I too, have a 3 year warranty, might get that fuel pump checked out.
Have you tried '96 octane?


Thanks for that Grolschie,


Will

[grolschie]

'96 is good, but quality varies. I was using PowerPills with good success:
http://www.take-colostrum.co.nz/powerpills.html

I was told that putting foot down means little as the computer won't give it more gas than IT thinks is needed. I am not sure whether I believe that, and wonder if driving with foot hardly on the pedal results in more economy - as opposed to heavier foot with same performance.

[grolschie]

Actually I should say that those pills worked SO good that first go, my fuel filter got blocked so that the car wouldn't run and it had to be thrown away. There must've been a heap of crap in the tank and fuel line.

[wlc21]

To those whose GDI that sounds like a tractor at idle,

Including mine, it jerks as if I had hydraulics installed!
It starts to jolt violently when the rpm drops < 750.

Well, my guess is to tune it above that 750 rpm mark and the car
should be stable, of course, the car will drink a lil' bit more - totally contradict the concept of economical fuel consumption huh ><

Open for any other possible solutions.


Cheers guys,


Will

[grolschie]

Hey Will, why not take it into a Mitsubishi Service Center? If you have one locally that is? Jerking sound like it's running on only a few cylinders at low revs.

My local MSC has two workshops, but only one will deal with GDI cars because it's specialized. My guess is that it needs to go on the computer to diagnose. Sounds like something is wrong in the GDI (whether a blockage or a sensor or something needs replacing). Tuning the idle is like sticking a bandaid on an infected festering gaping wound. Best to figure out why it's running so bad. Are you running high quality platinum sparkplugs?

[grolschie]

Plugging into the computer should tell you a stack of things. Even old VP Holden Commodores have a stack of diagnostic info to be read by attaching to a pc.

[grolschie]

Just wondering..... how much fuel does the air conditioning unit on these suck? Does it affect consumption by a huge amount or only about 10%?

[Hoppy]

Originally Posted by grolschie

Just wondering..... how much fuel does the air conditioning unit on these suck? Does it affect consumption by a huge amount or only about 10%?

Round town air conditioning will hurt - both in power and in fuel consumption, expecially if you run it on max fan/min temp.

On open road, if you set it to a comfortable temp (not minimum) and low fan speed and leave it running it should make bugger all difference to economy. I have had 3 cars with aircon and I have never noticed a hit in economy with aircon running on long trips. It is certainly more efficient than the drag caused by having windows open.

If your aircon is consistently costing you more than about 5-10% (that is about a loss of 1km/l) then something is seriously wrong... my bet is less than 5% would be normal - that will be hard to notice.