what would cause some ridiculous fuel consumption?

I have noticed I fill up a lot so did some tests.

I only managed to drive 165KM on 23.36L which is a fuel consumption of around 14L/100KM or 7.06KM/L

Surely that is a bit high for an Evo.

How do I bring this down? Its my daily and its costing me a fortune in petrol.

 

Stay out of boost and get your car tuned for starters.

 

I had the same problem after my build and it was a leak.

 

what kind of leak?

 

... dont step on your gas pedal that much? control your foot :P I can manage to drive 250miles to the tank... and that's with E85.

 

Those Ks where in normal city streets, no motorway driving but not stuck in traffic. My commute is pretty free flowing most days.

I try not to boost too often, takes the majority of the drive to warm the oil up

 

A bad o2 sensor could cause this issue. Is your CEL on?

 

^^ Actually, a lot can cause this. leaking injectors can be one too, right?

 

I would start ruling things out as people mentioned above. Ensure maf is clean, ensure air filter is clean, fuel leaks, etc....

 

I had a K&N filter and the oil had coated the maf sensor. I was getting about 10mpg for awhile before I cleaned it. The maf honeycomb is supposed to be white. I did not know.

 

I have no CEL on but car has done 200,000Ks+ so I might replace the O2 sensor for maintenance anyway.

Will check the MAF this weekend, grab myself some MAF cleaner and get it a good going over. Im sure it isn't leaking any fuel around the injectors but I don't know if they are leaking internally.

I sometimes get pops or a mild bang between slow shifts if im granny driving. Don't know if that has anything to do with it.

 

I do about 400k per tank which somes down to 180 for a track day

 

do you happen to have a wideband? it does sound like it's loading up on fuel.

 

Pops & bangs? Might be a good idea to throw in some new plugs too

 

I would be very happy with 400ks. Is this for an Evo 5 too? At the moment I would be lucky to get 300 and that is with driving sensibly.

Kaj, No wideband on it but I should be able to borrow one.

FossilAus, Yep get a pop on a slow gear change, no pops if I smash through the gears. Will change plugs for good measure, didn't change them last service as they "appeared" to be fine.


So far ill start with the easy options. I have Friday off work so will get investigating. MAF, plugs and visable fuel leaks first then ill track down a wideband if none of those appear to be not up to spec.

Car is reasonably stock, stock tune, TD05 20g turbo, 1 bar boost, front mount and a pod filter so I don't see one of those mods effecting fuel econ especially if I am trying to drive to save fuel on my commutes.