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VT Calais international fuel issues

V

VTinternational

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Hi guys
i bought myself a VT Calais international supercharged VT a couple of weeks ago.
The car goes like a dream but the fuel economy is killing me.
i know its not running right as i was getting 18 to 19L/100km...im not a car buff but i know that is damn high.
Been driving it decently and not flooring it and have managed to get it to around 16.5 L/100km's...still too high.

Need advice on what could be the issue and what i might need to do to get it running better.Would a bigger exhaust help in any way...i.e mild steel 2 1/2 inch straight through?....Also been told to maybe change the Petrol Filter as well.

Any advise would be appreciated.
cheers
 

Scooter79

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What sort of traffic conditions are you driving in? Heavy city peak hour or open highways. Remember that if you fill up and reset your trip computer your economy will look really bad. Usually takes about 30 - 40 kms to average out.

Don't spend big on exhausts. That won't fix the problem, only mask it and won't really help anyway. May need to replace fuel filter, air filter. Check your spark plugs. If the sparkies are pretty black then it's obviously running too rich. Could be bad oxygen sensors.

The VERY FIRST thing to do is a fault code check. Theres a plug under the steering column. Do a search on this forum for how to do it. It's been covered so many times before.

Filters and spark plugs are cheap though. Change them every 20,000k's.

You didn't tell us what sort of engine you have...
 

accentstencil

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Old oxygen sensors can cause bad fuel economy. They should be changed every 80,000 - 100,000 kms because apparently the loose their efficiency after a while.This may not be your problem but it was for me. How many kms has your car done?
 
V

VTinternational

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Scooter79 said:
What sort of traffic conditions are you driving in? Heavy city peak hour or open highways. Remember that if you fill up and reset your trip computer your economy will look really bad. Usually takes about 30 - 40 kms to average out.

Don't spend big on exhausts. That won't fix the problem, only mask it and won't really help anyway. May need to replace fuel filter, air filter. Check your spark plugs. If the sparkies are pretty black then it's obviously running too rich. Could be bad oxygen sensors.

The VERY FIRST thing to do is a fault code check. Theres a plug under the steering column. Do a search on this forum for how to do it. It's been covered so many times before.

Filters and spark plugs are cheap though. Change them every 20,000k's.

You didn't tell us what sort of engine you have...

thanks for the advice
i did the fault code check with a mate of mine tonight and we got a code 12 (which if im not mistaken implies that its all fine...correct me if im wrong)

driving conditions are pretty standard a bit of city driving and highway driving
also reset trip computer and actually my reading dropped the lowest sofar...got 15.5L/100km

anyway will see how it goes over the next couple of days.
Just a question in regards to fuel efficiency....hos many km's out of a tank should i actually get "technically" with a supercharged V^....does 400 to 450 sound reasonable?

cheers
 

Scooter79

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VTinternational said:
thanks for the advice
i did the fault code check with a mate of mine tonight and we got a code 12 (which if im not mistaken implies that its all fine...correct me if im wrong)

driving conditions are pretty standard a bit of city driving and highway driving
also reset trip computer and actually my reading dropped the lowest sofar...got 15.5L/100km

anyway will see how it goes over the next couple of days.
Just a question in regards to fuel efficiency....hos many km's out of a tank should i actually get "technically" with a supercharged V^....does 400 to 450 sound reasonable?

cheers

Don't know about you but mine has a 73 litre tank. If you're averaging 15.5L/100ks then that will only get you around 400 to 450 yeah. L67's hate city driving. At least in my experience they do. I do mostly peak hour driving on week days and get around 14L/100ks give or take a bit.

Remember when you do a fault code check that each code flashes three times before giving the next code. I had a faulty Throttle sensor on the weekend. Did a code check which means all ok. Kept watching the flashes then eventually flashed a 19. Do another code check and keep watching for the flashes.

Does the car feel like it's lacking any power? How long you had the car?
 

andrewgrazier

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VT COMMODORE 50th ANNIVERSARY
i was talking to someone the other day
n they said that theere wasnt a great deal of difference in fuel ecconomy between v6
supercharged v6 and v8s in models up to vt

i have noticed that my car chewes the **** out of fuel in city traffic
ie driving in sydney
but as soon as i get out
ive managed to get about 8 l per 100 kms on the freeway
 

Tree cutter

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Are you running 98octane fuel in it. When i bought my Calais the yard filled it up with unleaded which my car just drank in no time, and was very fumey as well. I filled it up with BP Ultimate and it is heaps better on fuel and no more fumes.
 

Scooter79

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andrewgrazier said:
i was talking to someone the other day
n they said that theere wasnt a great deal of difference in fuel ecconomy between v6
supercharged v6 and v8s in models up to vt

i have noticed that my car chewes the **** out of fuel in city traffic
ie driving in sydney
but as soon as i get out
ive managed to get about 8 l per 100 kms on the freeway

Same here. I assume you have a supercharged 6?
 
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