My fuel usage woes

S

Stuii

Leaving Skid Marks
Location
Victoria
First Name
Stuart Lowe
Drive
Mint ass Legnum!
Hi All,

I know I've been having a bit of a high profile lately, ever since I got my car in fact...

I'm now back on the road - but I'm chewing through the juice! 20L/100km!!!! I'm horrified a bit (again)

Since the car was a bit modified by the previous owner I'll post up the mods:
-HKS Pod Filter
-AVCR
-SAFC II
-TEIN Coilovers
-RDA Discs and 'Endless' pads
-Trust intercooler and piping
-Trust 3" dump pipe and front pipe
-RSR Full exhaust
-And of course it now has an as new gearbox from the first disaster

My first thoughts were it's probably the tune and boost, so since I'm running in my gearbox I figured I'd revert to stock for those two things - so I've got the SAFC set to a passthrough program and the AVCR set to .8bar

But that didn't help!

What left on that list could be causing it? or could it be something completely out there like the cams being out of phase or something (presuming when he got the belt done that the mechanic screwed it up)

Please give me your thoughts guys, This car is going to turn me into a serial killer if this keeps up :crying:
 
Had the EXACT same fuel economy, changed over the 02 sensor (yes, I know its the obvious one, but it is USUALLY the case) and now getting 14L/100Km
Some guys on the forum are getting as low as 11/100 but they are just lucky, 14 is normal
 
cool, I know someone who is being kind enough to maybe lend me a spare sensor so I might give that a go this weekend (y) fingers crossed I guess...

how much are they new?

any other leftfield ideas people can think of?
 
Tune the SAFC for low throttle settings and piss off the pod filter.

Chances are, that when that duuuude who you bought the car from had it tuned, they would have only tuned it for boost and at high throttle (+50%). You will find that you would do most of your driving below 50% and therefore, the SAFC is doing nothing but looking pretty.....
 
If you tune the SAFC for low settings you will be always fighting the closed loop setting of the ecu. I was advised to just tune my one on the high setting
 
First pick for me would be the O2 Sensor,

If the pod filter isn't correctly sorted that could be adding to the problem if its upsetting the airflow going through the MAF sensor, that could be causing the ECU to overfuel.

to upset you even further I get between 8.8-10L/100k as a comparison, though mine is completely standard, but just so you know what they're capable of.
 
Kitty's VR4 said:
First pick for me would be the O2 Sensor,

If the pod filter isn't correctly sorted that could be adding to the problem if its upsetting the airflow going through the MAF sensor, that could be causing the ECU to overfuel.

to upset you even further I get between 8.8-10L/100k as a comparison, though mine is completely standard, but just so you know what thery're capable of.
Click to expand...

You're just l;ucky!! Surely the series 2 are going to get worse economy over the series 1 due to the higher kw's though? (not that much, granted, but still a little)
 
Hey Stuart, I got about 200kms out of my first few tanks. After I did the basic service such as plugs, leads, O2 sensor etc and got over the initial driving excitement I'm now seeing 400km+ per tank.

You probably wont find someone to swap you an O2 sensor, as they can be damaged easily and also have a one-time use compression washer on them.

It looks like the Sale & Wonthaggi stores have one each, go to your local store and hassle them to order it in for you. It was a run out item for about $30 and they are almost all gone, but check store stocks below:

http://www.google.com.au/search?q=OZA116-M8+%2BRAP&hl=en&rlz=1B3GGGL_en___AU221&filter=0

EDIT: The O2 sensor is NTK OZA116-M8 . . . $29.00
 
As the previous guys have stated it could also be in the SAFC, but I don't have a detailed understanding of SAFC's so that should also be considered

I'd actually think the Series 2 might be capable of better figures because of a leaner fuel map in the 7202 and 7203 ECU's, plus this just means I have to get up it more to keep up with you guys in the series 2, even on club runs the guys will tell you I don't baby it and I still get in the 10's, actually alot of them on club runs will tell you that include spirited driving that they seem to get they're best consumption figures...

so for me

1. O2 sensor
2. Pod filter
3. SAFC as the other guys have eluded (this may also belong on top of the list - but I'm not sure about them)
4. maybe it will appreciate a spirited run once you've bedded the gearbox in
 
Notice those words though....stock standard.......as soon as you put in a FMIC, full exhaust etc etc your fuel consumption is going to go up...I know as soon as I hard piped, FMICed, boosted etc.........fuel consumption went up...I did have a Haltech in so I was able to control timing as well.
Have you reset ECU? Oxygen sensor can be bought at Repco...search old threads for which you need.



Kitty's VR4 said:
First pick for me would be the O2 Sensor,

If the pod filter isn't correctly sorted that could be adding to the problem if its upsetting the airflow going through the MAF sensor, that could be causing the ECU to overfuel.

to upset you even further I get between 8.8-10L/100k as a comparison, though mine is completely standard, but just so you know what they're capable of.
Click to expand...
 
I was referring to yours... hope you didn't mind, I figured your offer would still be open...

is there 1 sensor or 2 in this car and where is it?

I know I sound a bit, dumb - I'm not a complete moron, but I have no idea of the layout and such of these things
 
Yep, you can give it a shot. Let me know when you wanna try it.

Remember how you saw my passenger side tunnel cover was off. That is how you get to the plug. Unclip it there and it is right under the Cat. Takes 10 mins to swap over.
 
carnarvon repco in wa had an ngk left that you could always get posted and itll still be heaps cheaper.
I just put a bosche one in, 97 from repco. Took 10 min to swap it over and solder it up once id got the old one out. Getting the car high enough to work on took the longest time
 
1. Oil Change
2. Plugs
3. O2 Sensor
4. Injector clean or full service of them.
5. Standard air box
6. Tune the SAFC to Aussie 98 RON fuel.
7. Drive with your foot 1 inch above the accelerator pedal.
 
What everyone else said, although I have to give extra points to Pete for putting it into a nice little list :) I'd move std airbox to the top though.

I disagree about the intercooler and exhaust making the car use more fuel. I found that with my exhaust on I had better fuel economy, infact I was able to do 640km to about 53 litres once with my full front pipes back exhaust. No cat though....and before anyone asks, yes this was back when my purple car was an auto and completely stock apart from the exhaust.

The intercooler will only cool the air more, which in turn means less knock, so in turn you use less fuel.

An safc will help, but only when you are making boost and getting a move on, so it won't really affect you if you are driving slowly.

Don't forget to check your tyre pressures, they should be around 36-38psi IMHO.

Lastly, the boost controller will only affect fuel consumption if you are going over the stock boost levels. I still regularly acheive 10-11l/100km in my purple car and that is with 228kw and 445nm of torque....AT THE WHEELS. Conversely, around the Taupo racetrack, it uses about 42-44l/100km :D


Ohh, forgot to say, I disagree with your first line, it wasn't ever since you got the car, it was about 30km afterwards :) /runs!
 
OK Pete, I'll definitely be oging throught he things on that list...

something weird happened on my way home... I went to fill up because mmy gauge was reading about 3/4

full till was 34.5L and I have travelled 230KM
that works out to 15L/100k

I haven't done anything different...

still this is damn weird why would I read at 3/4 when I've only used a smidge more than 1/2?

scottie is going to lend me an o2 sensor tonight, but since it's raining I might have to wait till the weekend to install it... unless I'm lucky tonight
 
The fuel gauges are a bit inaccurate and bounce all over the place. Simply drive it a bit further next time and wait until the light comes on. If the light hasn't come on by the last line on the dial then pop into a petrol station.
 
just wanna add something too..

use the correct oil viscosity..

I've noticed that with the 5w40 my economy isn't that good.. (was only doing 350kms)

but ever since I've changed over back to 0w30, my fuel gauge needle is still about 3mm away from the last quarter and I've already done 330kms.. so I'm looking forward to doing 450kms again..

in my opinion oil viscosity does make a big difference/effect on your engine's fuel economy..
 
You must log in or register to reply here.

Similar threads

K
Suspect fuel pump failure
2
Replies
23
Views
3K
mezje
mezje
Wantedlobster
Fuel and ignition not working
Replies
2
Views
666
Baba Galant
Baba Galant
Lasiorhinus
Water in Fuel
Replies
2
Views
802
Lasiorhinus
Lasiorhinus
kc427
"Target AFR" not showing the correct fuel map table value?
Replies
11
Views
4K
GLen20
GLen20
L
Dropping fuel tank; what else?
Replies
3
Views
1K
Leggie
L
Top Bottom