Poor Fuel Economy Gtr

[gtrzilla]

My GTR R32 seems to have quite bad fuel economy

Car is completely Stock Standard!

Running it on BP ULTIMATE only!, tank is approx 63 litres i think

Now that usually gets me b/w 300-350 km ( 300km with a bit more booting it around)

Seems horrible for the odd 100 bucks of fuel to get u about 325km

My mech (ray at RE) mentioned that i have a slight injector leak in one, could this be the cause.

What do ppl get out of their GTR's (km's)

[godzl1975]

slightly modded GTR full tank around 350km mark...standard should be able to get the 400km mark...but depends on driving style i guess.

[ali-turko]

i used to get what you get out off 300kw gtr

[infamous_t]

I used to get 350km to a tank but since I had my 100K service (except o2 sensors) i've been getting 400Km on the nose.

Generally get that if I drive like grandma, or thrash it...

I believe new o2's and a tune 'should' better this(in my case anyway), but Ill have to wait and see.

[Amec]

other causes of bad fuel economy are:

- faulty engine coolant temp sensor

- faulty knock sensor

[gtrzilla]

i know that there is an injector leak on at least one injector

could this be a big cause of fuel consumption

[GeeTR]

i know that there is an injector leak on at least one injector

could this be a big cause of fuel consumption

It'd had to be a pretty serious leak i would think. Clean the stains around your leaking inj and see how long it takes to reappear. To see what its like on boost (base fuel pressure + boost) you could feed the FPR 1bar from a air compressor with regulator set... to 1bar

Edited February 26, 2008 by GeeTR

[WOG BOY]

urs is as bad as mine....i have a completely stock r33 gts-t and i did 244km's of hi-way driving....(only 100km/h no booting or speeding) and that cost me $40....

imo that is really really really bad......what should i be looking at doin? complete service or a tune or both.....where should i take my car? or replace what and sutff....it killing my pocket!

plz help!

[stolen_s15]

Check the basics first

Clean air filter

Replace fuel filter

Check (and if necessary) replace spark plugs with correctly gapped new ones.

Check health of coils, replace if needed.

Clean AFM

Check 02 sensor

You got standard diff gear? If not that could be f'ing with your economy

Clean Idle control valve (or whatever its called on rb26)

Run some fuel injector cleaner through.

Get injectors ultrasonically cleaned (should cost not more than $120)

Your fuel leak will be effecting economy, to what extent depends on the size of the leak

I did all of the above on my car and noticed a big improvement.

[HELLRAISER]

urs is as bad as mine....i have a completely stock r33 gts-t and i did 244km's of hi-way driving....(only 100km/h no booting or speeding) and that cost me $40....

imo that is really really really bad......what should i be looking at doin? complete service or a tune or both.....where should i take my car? or replace what and sutff....it killing my pocket!

plz help!

mmmmmm mate

240km with 28ltr (proximetly $40buck worth) of petrol it means 14ltr for 120km

i reckon that is NORMAL for Gts25t, i get about the same

*power comes from burning petrol

[MYRB30]

I get 400-450km out of my R32 GTR, around town. On highway I can get around 11-12 litres per 100. I am a mechanic so everything is pretty well spot on. A stock GTR for economy should be tuned as Nissan says, not the local dyno shop who has retarded your timing so you can have another 20 horsepower.

[gtrzilla]

I get 400-450km out of my R32 GTR, around town. On highway I can get around 11-12 litres per 100. I am a mechanic so everything is pretty well spot on. A stock GTR for economy should be tuned as Nissan says, not the local dyno shop who has retarded your timing so you can have another 20 horsepower.

wouldnt they advance your timing for more horsepower ????

and btw my car is stock as a rock

so no tuning necessary

out of a full tank around town i got 330km?

[gtrzilla]

Check the basics first

Clean air filter

Replace fuel filter

Check (and if necessary) replace spark plugs with correctly gapped new ones.

Check health of coils, replace if needed.

Clean AFM

Check 02 sensor

You got standard diff gear? If not that could be f'ing with your economy

Clean Idle control valve (or whatever its called on rb26)

Run some fuel injector cleaner through.

Get injectors ultrasonically cleaned (should cost not more than $120)

Your fuel leak will be effecting economy, to what extent depends on the size of the leak

I did all of the above on my car and noticed a big improvement.

i have had a major service

new plugs

new fuel filter

oil filter

all the usual

car is running mildly rich, but not as much to denote such bad fuel economy

im thinking maybe o2 sensor

are these expensive

[(OO)SKYLINE(OO)]

Hey Orian

Check your injector and change the one that might be leaking, then replace the O2 Sensor that is not working.

Also is the car a daily driver? If so do you always go the same route to work etc... Do ya go though a lot of heavy traffic?

Resently we have been having some hot weather... Can effect the cars performance ie. ya boost kicks in alittle later cuz its a hot day and so you put ya foot down more to get it going...

ALL just minor things but can add up in the end...

[MYRB30]

wouldnt they advance your timing for more horsepower ????

and btw my car is stock as a rock

so no tuning necessary

out of a full tank around town i got 330km?

True, advance timing to make more power, but if they wind the boost up it will ping, so wind the crank angle sensor back to stop the pinging, but still got high boost. So everywhere else in the mapping the timing is retarded, and hence more fuel usage.

[gtrzilla]

also like i said car is stock

however it is running about 10psi ????

[(OO)SKYLINE(OO)]

also like i said car is stock

however it is running about 10psi ????

Oh yeah BTW your Stock Boost Gauge should read -7 / 0 / +7 Bar

If it goes all the way up to +7 Bar then yes 10psi, WHICH I think the Brass Boost Restrictor has been removed (As we were talking on Saturday at RE Customs)

If the Restrictor was still in, it be reading a +5 Bar so Basicaly a factory saftey increase.

[gtrzilla]

yeah but taking out the restrictor makes your run 1 bar = 14.7 psi = 7mmHg (the stock gauge)

so i have no idea why its running kindof in the middle bewteen 7 and 14 @ 10 - 10.5 psi

maybe its just old

[(OO)SKYLINE(OO)]

^^LOL! Nah bro!

The Stock boost gauge is measured at -0.7 / 0 / +0.7 Bar.

So +0.7 Bar = 10.5 psi

N1 GTR's are the one that run 1 bar.

Edited March 4, 2008 by (00)SKYLINE(00)

[gtrzilla]

yeah thats why i said removing the restrictor makes you run 14.7 psi

not saying that is a good idea

what im saying is that the gauge is in mmHG not bar

7 mmHg = 1 bar