very bad fuel economy

[90xsi]

hey guys i got the car registered on monday and i filled up a full tank and only managed to get 270kms out of a tank driving very conservative. i've searched and it seems to be pointing at my 02 sensor. i plan on getting that changed asap. im just wondering is there anything else that i should be looking at? thanks in advance

Phi

 

[Jonson]

What car? What mods? Go get a scan done, it will tell you if there are any faults.

 

[Dean]

Could be o2 sensor,
could be a bad tune, which means its running rich.
Is there black out of the exhaust?

 

[milkandoj]

heres some threads i could find. Keep searching there was another recent one that was pretty good also.


http://4gtuner.com/site/showthread.php?t=15148&highlight=fuel+economy

http://4gtuner.com/site/showthread.php?t=8729&highlight=poor+fuel

http://4gtuner.com/site/showthread.php?t=10936&highlight=fuel+economy

http://4gtuner.com/site/showthread.php?t=12212&highlight=fuel+economy

 

[90xsi]

car is a gsr with afas rebuilt evo 3 motor.
just a 3 inch catback exahaust. still running stock boost.
car pops on idle but doesnt blow smoke.
blows alotta black smoke when coming on boost
thats all i know atm. im gonna try ordeer an o2 sensor
and i guess just see from there how i go.

 

[terbulent]

hey guys i got the car registered on monday and i filled up a full tank and only managed to get 270kms out of a tank driving very conservative. i've searched and it seems to be pointing at my 02 sensor. i plan on getting that changed asap. im just wondering is there anything else that i should be looking at? thanks in advance

Phi

wish i got 270k's from a tank

 

[bazeng]

270 is what I used to get on my wolf.. 300 was a good day!!

It could be many things buddy!
From your injectors to your fuel pump to your fuel pressure reg etc..

Try and list as many mods as you can and we'can try to help you out with more accuracy..

 

[90xsi]

its just a forged 4g63 evo 3 motor running yellow top injectors with stock e3 ecu with gsr drivetrain. still running stock boost. honestly the only mod is a 3 inch catback. ive given it a full serviced including engine oil, gearbox, diff, transfer case, fuel filter, irridium sprak plugs and thats it so far.

Phi

 

[Entaran]

510cc injectors might need cleaning. o2 sensor is probably dead, try putting some compressed air down your fuel return line to blow it out, might be full of crap.

 

[bazeng]

Chuck on a fuel pressure gauge and see what base pressure you are at.

As Entaran suggested, you could have higher than normal fuel pressure for some reason.

Look at your o2 / afm / fpr / injectors

Also what tyres do you have?

 

[kb24]

im getting about 300ks now which is still not good im thinking injectors need a clean also cause ive tried everything else, but ive been askin a few of my mates about their cars and that seems an average figure for a 2lt turbo car, its hard to believe some people here get 450- 500+

 

[91LTI]

In my EVO II converted GSR, I get around 420-450km per tank. Most I've got was around 475km i think.

Though I do a fair bit of HWY kms...

If you are in traffic all the time then the go-stop-go will negatively affect your economy.

 

[Entaran]

Do you bychance always cruise around in third gear? I know plenty of people who do and it rapes your fuel economy.

 

[Richard]

Who gives a fuck how many km's per tank you do, how many litres are you putting in to get the km's you are doing, maybe you are filling it when there is still 1/4 tank left....

 

[Dean]

A nice tune will fix your fuel problems..

 

[kb24]

Who gives a fuck how many km's per tank you do, how many litres are you putting in to get the km's you are doing, maybe you are filling it when there is still 1/4 tank left....

mine works out to be 6.3k/1L

 

[rob323]

car is a gsr with afas rebuilt evo 3 motor.
just a 3 inch catback exahaust. still running stock boost.
car pops on idle but doesnt blow smoke.
blows alotta black smoke when coming on boost
thats all i know atm. im gonna try ordeer an o2 sensor
and i guess just see from there how i go.

The O2 sensor only comes into play when cruising (and the ecu goes into closed loop). It won't have anything to do with the black smoke when coming on boost.

Put a logger on it somehow and see what water temp it is reading. If the water temp sensor is giving off low readings, the ecu will be running richer than needed on all maps.

It would also pay to pressure test the intake for leaks as these will cause it to run rich when on boost, but won't affect cruising economy all that much.

Is the Bov a recirculating one? If not, check that it is not opening up under idle and allowing air to be sucked in fromt here.

Then do all the fuel checks as suggested previously. An evo3 due to the higher compression should be getting better fuel economy when cruising than a vr4.

 

[90xsi]

who could i possibly see to chuck a logger on my car or where can i get one from?. its still got the stock bov all plumbed back so nothing special there.

 

[bazeng]

Have you sorted this yet mate?

 

[90xsi]

yea all sorted.
now i get about 400ish a tank
thanks alot for everyones input

Phi