What can cause poor mpg ??

motfree

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Just wondering what is causing my car to use soooo much fuel even when I'm driving sensible ..
 
Alot of factors can make it worse - especially this time of year as its ****** freezing lol - also having a heavy foot, but if your driving sensibly im not sure what else to say....
 
WEIGHT
WIDER TYRES
DECAT
FAULTY SENSORS, MAF, COOLANTS, COIL PACKS..
FAULTY, THERMOSTAT
OVERDUE SERVICE
AIR-CON

HEAVEY FOOT
SHORT TRIPS
BOOSTING and HIGH RPM
 
Brand new Maf on 2 weeks ago ..
Maybe but it's using around £10 for 30 miles and that's not putting my foot down .. Think I'll go to a garage :) as I don't have a clue
 
I get the same, regardless of how carefull I am.

Just to add to the list. feel free to add your thoughts

WEIGHT
WIDER TYRES
DECAT
WORN CLUTCH causing slips. not power no go.
FAULTY SENSORS, MAF, COOLANTS, COIL PACKS..
FAULTY, THERMOSTAT
OVERDUE SERVICE
AIR-CON
SEIZING BRAKES.
WORN OUT BEARINGS


HEAVEY FOOT
SHORT TRIPS
BOOSTING and HIGH RPM

 
Actually my coolant sign keeps coming up on my dash ? Maybe that sensor is bust .. But why would this make it use more fuel :-S ??
 
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Blowing exhaust before the O2 sensor leaking more air in with the ECU thinking the engine needs more fuel

Boost leak and vacuum leak is also the same
 
Actually my coolant sign keeps coming up on my dash ? Maybe that sensor is bust .. But why would this make it use more fuel :-S ??


Im getting this only on very cold morning starts though. Anybody know what this is caused by?


Strange :S
 
It may be fuelling high as the coolant sensor is telling the ECU that the engine is 'cold' and as a result it is pumping a richer mixture through. I would try changing the sensor first, whilst you are at it, check your tyre pressures and also check the state of the airfilter (infact, check when it was last serviced and when it is next due for servicing).

EDIT: Coolant sign on the dash also comes up when the expansion tank sender decides that it wants to play up - a new one is about a tenner and should sort it out, oh and its nice and white, and not a light brown colour as they tend to discolour over time so it's easier to make a visual check of how much coolant you have in there.
 
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Tracking to cure poor fuel consumption Classic fella ,also check parcel shelf straps ,could be that too
 
Try the simple things first like wheel allignments and tyre pressures all correct.

Tracking to cure poor fuel consumption Classic fella ,also check parcel shelf straps ,could be that too


Mr fish, Hector is correct, wheel alignment can cause tyre scrubbing which needs to be overcome by engine power, using more fuel
 
If you say so ,go get tracking done then and see you in a week when you still have the same problem.
 
Tracking can cause higher fuel consumption but i think it would have to be way out though as said by bryzan the engine will be working harder to overcome the resistance caused by this its the same principle as binding brakes and low tire pressures.
 
If you say so ,go get tracking done then and see you in a week when you still have the same problem.

I do say so as it's fact.....

It is however unlikey that its changed that much without the driver noticing, but it can be a contributing factor if all else has been checked
 
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