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Discussion Starter #1
Got a 1.6 h design and it has a dramatic decrease in mpg. when i first got the car it wasent this bad. i used to get 39-41 but now with the usual journeys i get roughly 29-33.6 mpg and it shouldnt be this bad. i drive like a granny in order to save petrol.

e.g. i drove 7 miles and it took a fiver...

The car is in need for a service atm but i dont think it should be this bad.

can anyone recommend me a service type and tips on saving fuel...e.g. cleaning carbs etc
 

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You should try some redX to clean ur injectors as they could b full of crap!
do you hav any iratic idealing sometimes when you start the car up?
 

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You did not use a fiver of fuel to do 7miles mate. If it was using that much it simply wouldn't run..

33mpg really isnt that bad... are you taking that from the obc or working it out from reciepts etc.
 

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A.O.N. - Platinum Member
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You could check your tyre pressures, if they are out this could effect MPG
 

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A Murcielago does 8MPG round town so I seriously doubt your getting that mate, you must be working it out wrong :eek:
 

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Discussion Starter #8
The car acts up at times when starting and when it does, it goes up couple k revs then drops thats all... im using the onboard computer. I had my petrol light lit so i put in a fiva, then reset the obc. drove over 7 miles, parked up and the light was on again.

The fuel gage raises and lowers when it wants and say i park up... then in the morning, drive the car and i have less fuel.. no leaks or anything. im really confused...

I skip gears as i was told the the higher the gear the lower the revs... i dont think this seems to be working.

Roughly how many miles should a fiver do around town? and are there any driving tips
 

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Discussion Starter #9
also to add, the car needs tracking, could that be a cause?
 

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Right, you cannot trust the OBC mpg reading and the way you have worked out 7 miles to £5 is totally inaccurate.

This is what you should do:

1. Fill your car up with fuel to the very top of the filler neck so that you can see it.
2. Reset your trip computer before moving.
3. Drive as you normally would until you have nearly used the tank.
4. Fill your tank back up to the exact same spot so you can see the filler neck is full.
5. Note how many litres it took to fill back to the same point, convert this to uk gallons. Then divide the miles you travelled by the gallons you had to put in the tank.

This will give you an accurate reading of mpg over 1 tankfull. Do the same over a few tankfulls to get yourself an average (Y)
 

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Right, you cannot trust the OBC mpg reading and the way you have worked out 7 miles to £5 is totally inaccurate.

This is what you should do:

1. Fill your car up with fuel to the very top of the filler neck so that you can see it.
2. Reset your trip computer before moving.
3. Drive as you normally would until you have nearly used the tank.
4. Fill your tank back up to the exact same spot so you can see the filler neck is full.
5. Note how many litres it took to fill back to the same point, convert this to uk gallons. Then divide the miles you travelled by the gallons you had to put in the tank.

This will give you an accurate reading of mpg over 1 tankfull. Do the same over a few tankfulls to get yourself an average (Y)
^Only way to do it accurately:thumbs:
Also have you checked the air filter? A blocked up air filter can result in heavy fuel consumption, if the car is due a service......get it serviced! Look after the car it'll look after you :thumbs:
 

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41 MPG out of a 1.6 petrol is very good, the rated consumption according to the NEDC cycle (which is run with the engine in a test bench) for that engine is 36 MPG. You havent taken the numbers from the computer have you? Because the computer has no idea how much fuel it's using to get anywhere, it's just guessing based on the only factor it knows, your throttle input.
 
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