My N/A Auto VL seems to be chewin through the fuel. After reading some web sites I should be getting like a 11km/litre... Well I'm gettin about 280km/Tank. What should I be getting and how can I diagnose the problem out? Would it be the computer by anychance? My Fusebox went just a while ago and before that I got a 100kms to a quarter tank. I would diagnose the computer but I dont really know how to do it. The thing is the engine sounds and goes fine....Also my fuel pump is noisy. Is that bad? I've only had my VL for 2 weeks, so I dont know to much about em as yet, but I do have a basic mechanicle knowledge of cars!. Thanks

should get about 450 kms to a tank easy... as for what could be wrong - i'd say check the ECU codes to see if anything was coming up on it... maybe someone else can clarify how to do this exactly, as i've forgotten how to do it myself...

Get hold of a manual either buy it or borrow one. It tells you how to check your fuel/air mixture. Make sure it isnt running rich, check for leaks or anything like that (does the power seem ok or sluggish?). I am getting about 350kms out of a tank thrashing it, and about 400kms a tank steady driving. I use premium and run 20degrees BTDC timing. Car: 1987 VL Commodore SL Extractors + 2 1/2" sports zaust Cold air intake.

The two main culprits would have to be: The oxygen sensor, if its the original it will be very sluggish to sample the exhaust gases and closed loop operation will suffer severly. So that can be replaced. And generally if the temp sensor fails it acts like a choke so your car runs rich all the time. Get a manual for the testing procedures. Mick

yeah, i just got about 300ks on half a tank today (highway driving @ about 100-110) and was pretty pleased... but even thrashing it you should get 400+ ks Some original photos have not been recovered yet.

well i get about 230km outta $20 without the mesh screens in the airflow meter and i clean the air filter once a fortnight. on top of what the other guys said, something simple like a dirty air filter will decrease economy so replacing that can do a little bit also try the simple things like checking the o2 sensor, afm connections etc and give em a clean and replace if necessary if a problem still exists, at least you know that youve done the simple things that cost next to nothing to try to locate the cause theres nothing worse than spending $$$ to find out the problem by replacing big components when a simple clean of something may be the answer

yer unless ya rich then replace it all, if not then take it to an efi specialist. For under $100 you can get it all looked at plus some stuff replaced.... my auto goes like **** on fuel, then i got a manual vl and its WAY BETTER on fuel..........

Be sure its not your fuel level sender unit. When i first got my VL i thought crap! gunna have to sell it if its going to use this much fuel. Filled it up the day i bought it and drove it home, ended up doing about 200k's and it was on quarter of a tank. So i drove it till it read near empty (about 300k's all up) then went to fill it up. Only cost me about $20 or a little over (was a while ago i forget exactly). So after a few more days of this i realized that the sender unit must be faulty and sending the gauge wrong signals. Basically half a tank of fuel was reading as quarter. Might not be your problem but was just a thought.

Cool...Thanks guys, looks like i'm buying a manual tonight! I did a computer diag and the only code i got was code 11 (CAS) well i dunnno about that, my engine starts all the time and as far as i know and that shouldn't have any impact on the fuel econmy. Last night I've just put $15 of optimax in. Should I notice a difference at all?? I'm also thinking of buy some spitfire to clean my injectors out. I know this probably wont fix the problem but it definatly wont do any harm. I'll have another look at the oxygen sensor tonight and buy a manual to diagnose it. Is there any recommended oxygen sensors to buy? if so how much are they approximate?

Yeah my fuel trank senser is knackered also... I'm getting about 12L/100km which i believe is fairly decent for city driving, even better on the highway but i'm yet to check the difference. But that will all change if I can get this turbo commorore I'm lookin at buying, hehe . Some original photos have not been recovered yet.