Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Terrible fuel economy.

Jhawt96

New Member
Joined
Jul 28, 2013
Messages
2
Reaction score
0
Points
0
Location
Qld
Members Ride
Vs executive
Ok so I have tried absolutely everything to try and improve the fuel economy out of my 96 vs sedan and nothing has worked at all. If anything it's getting worse! I'm lucky to get about 150 ks to a tank! And today I actually ran out of fuel so I'm not happy! Like I said I've done everything, changed oil, fuel filter, oil filter, cleaned fuel pump assembly, so had the tank out, cleaned original O2 sensor earth on engine block and then re earthed them at the ecu as per the how to on this site. (Though I did only run the earth to the body, could this make a difference?) if anyone could help it would be great because I'm sick of throwing money away! Oh and there's no error codes showing. Cheers.
 

Drawnnite

Obviously Unsensible
Joined
Sep 2, 2010
Messages
1,651
Reaction score
629
Points
113
Location
Victoria
Members Ride
2000 Vs Ute
maybe a suggestion. grab an aldl cable and tunerpro and hook it up, see if anything shows up on that.
might be able to show you what could be causing the issue.
 

MRNICK

LS1 LOVE
Joined
Mar 5, 2013
Messages
122
Reaction score
1
Points
0
Age
32
Location
Newcastle, NSW
Website
www.holdenowners.com
Members Ride
VYII SS UTE
I'd be replacing the 02 Sensors. I'd put money on it being that. Earthing them is all well and good but unfortunately this doesn't really change how well a fouled up sensor will read.
Also, spark plugs and spark plug lead efficiency will determine fuel economy.
 

Jhawt96

New Member
Joined
Jul 28, 2013
Messages
2
Reaction score
0
Points
0
Location
Qld
Members Ride
Vs executive
I have replaced the plugs and the leads was the next thing on the list. The car needed a good service anyway. But I'll look into buying new O2 sensors. Hopefully this fixes the problem.
 

evBenji

Well-Known Member
Joined
Dec 22, 2010
Messages
1,104
Reaction score
70
Points
48
Location
Adelaide
Members Ride
VY Commodore
I have replaced the plugs and the leads was the next thing on the list. The car needed a good service anyway. But I'll look into buying new O2 sensors. Hopefully this fixes the problem.
i too just got a VS recently, and have been pretty disappointed in the fuel economy, after having a VL

Last week just got a service, with all the key points purchased, most fuel filter & new oxygen sensors

i also did a study on what things could be done to fix it here...
My fuel economy study

All excited about getting it tuned up, i return to pick up the car last week, all to hear that my exhaust manifold has a crack in it grrrrr

and theres my fuel loss right there grrrr
 

Ron Burgundy

Well-Known Member
Joined
Jun 3, 2004
Messages
4,116
Reaction score
3,022
Points
113
Location
NSW
Members Ride
VF II SS
torch it....
 

Brett_jjj

Well-Known Member
Joined
Oct 16, 2009
Messages
6,805
Reaction score
96
Points
48
Location
Tamworth NSW
Members Ride
vs commodore
Ive found that I can get excellent fuel economy from my VSV6 by keeping everything serviced etc. Engine oil and filter, auto trans filter and fluid, air filter, fuel filter, plugs, leads, the 3 ignition coils and the 02 sensors. Keeping the MAF clean with MAF cleaner, keeping the throttle body clean and cleaning/replacing the fuel injectors every 150,000 or so km. All these things mentioned will make hardly any, or only a very small difference on their own, but when all the small differences are added up, it makes one big considerable difference, especially to fuel usage.
Wheel alignment also makes a huge difference to fuel usage over time. Get the alignment set to factory specs with the measurment (caster angle) absolutely dead even on both sides, and this will help a lot with using less fuel. Keeping the tyres pumped up to maximum pressure will also help. Also check for dragging brakes (including handbrake shoes) or binding wheel bearings and uni joints..
Ive also found that using 98 octane fuel (even with the standard tune) makes a big difference to the fuel ecomony of my VS and my VY wagon, and I go further on the 98 octane fuels, even though I get less of it at the bowser as its more expensive..
If your vehicle is not running 100% correctly to begin with, then you probably wont notice any difference at all, if you like to plant the right foot a bit, then this is where the 98 fuels really come into their own, and the vehicle will use way less fuel than it would if were driven the same way, but on 91 octane fuel..
I can get anywhere from 6 to 8 litres per 100 km out on the highway, and anywhere from 8 to 12 litres around town driving normally. I only ever use 98 octane fuels, and with the tune im running in the VS, the ignition timing values are bumped up a lot higher over the standard values, this is so the engine can take even more advantage of the 98 octane fuels, it also holds the timing for longer when under load before the ECU detects any knock and then retards the timing. When on 91 fuel, it drops way more timing than it does on 98 fuel, but as I said above, even with the standard tune, you should see a fair difference between 91 and 98 fuels, thats if your vehicle is running 100% correctly to begin with of course, but increasing the timing values in the tune just tops it off nicely, and, as well as saving fuel, it also makes the engine a lot more responsive and just better to drive. Ive also got pacemeker tuned length extractots fitted, which again, helped with fuel usage. I also had problems with standard passenger side exhaust manifolds cracking, I went through 4 or so of them, that was one of the main reasons I fitted the pacmakers, and havent had a problem with it since.
 
Last edited:
Top