petrol gauge and fuel economy

[vroomm]

Bought a fairly shitty commodore VL exe for $1500 and have driven up and down the east coast in it. Used to be getting more than 350K cruising on a full tank but since I left byron bay I've been getting 230K. Petrol prices being what they are this is killing my funds. To make matters worse my petrol gauge doesn't work. The first time I found out about this drastically reduced fuel economy I was lucky not to get stranded in the middle of ****ing nowhere.
The gauge sometimes works - usually in the morning; but even then I've never seen it go to more than half - even when I know theres a full tank. It goes back down to empty after I've driven it for a while.
Any ideas whats going on with that?

Apart from this I'm fairly happy with it - recon I've got good value for money.

by the way, selling it in Cairns in around two weeks if anyones interested

[detox_nath83]

Yeah may be your float level in your tank where the pickups are, might even be a faulty gauge.
it sounds like it is running rich if its burning fuel quickly, possible causes is the air flow meter might be on its way out(is there a bit of smoke when u floor it, i had this problem and was the air flow meter) Also it could be the engine temp sensor, not disengaging when the engine gets warm it still thinks the engine is cold and runs rich. Check the sensor terminals for corrosion.... thats all i can think of atm, good luck

[exec57l]

Air flow meter, oxygen sensor and water temp sensor are the main reason for poor consumption in these engines.

I swapped the AFM and oxygen sensor in mine and gained about 80 - 100 kms per tank.

[holdensupporter2005]

Install a cold air intake in the air box, Put in a K&N air filter in, check your air flow meter (you can check this with a multimeter, on pin 1 and 6 of the air flow meter, should be around 382 ohms.
Try also changing your fuel filter.

Get your injectors cleaned is another option but an expensive option.

also try putting some NULON Injector cleaner in your fuel tank. this will help to clean out your fuel system.