amazing disappearing fuel trick!

[White2505 0]

So I'm currently getting about 20mpg out of my valver.

 

There are no fuel leaks, it has new injectors fitted and dioes not appear to be running rich, I recently had mixture checked and the plugs look real nice so there is no evidence of over fueling at this point. idle is good and power is okay though not great. ECU is known to be good as it's recently been swapped out.

I have a replacement CSV on its way also.

 

so the question is how can I be using SO much fuel without running rich.

[Walesy 0]

not being gay mate, but are you sure the car is using so much fuel?...as in is that just what the MFA says or have you also noticed it using loads of fuel.

 

 

Could be a few things if it is running rich, lambda sensor for one.

[White2505 0]

Hi,

 

mfa is already goosed on mpg, this is from actual fuel usage and actual mileage covered. Most people seem to be average in the mid-high 30's unless they're having troubles so I know my fuel consumption is WAY too high.

 

there is no lambda sensor cos its a 1.8 valver. I just don't see how i can use almost twice as much fuel as the average without obviously running rich???

[bcstudent 0]

I only get about 30-32mpg average from my 1.8 16v, which annoys me greatly since it's not that fast. 20mpg does seem excessively low though.

 

If it's not using the fuel it must be losing the fuel. Check for leaks around the main pump housing and where the fuel pipes join in the engine bay; both places mine has leaked from in the past. It's also possible the fuel tank is damaged and leaking.

[ben16v 0]

got an avarage of 34 mpg over 400 miles today in my valver so i`d say 20 is a bit low

 

ben

[White2505 0]

definately no leaks around the fuel tank, pump, filter etc, in fact I replaced filter yesterday.

 

Is there anyway for fuel to pas through the engine without being burnt and without igniting within the exhaust pipe??

[bcstudent 0]

Is there anyway for fuel to pas through the engine without being burnt and without igniting within the exhaust pipe??

I'd be very surprised.

[Neil VR6 0]

Sure you're not driving a G60?! :lol:

 

The easy way to find out how many MPG you're doing is to fill it up, run it nearly dry and then divide that by how many gallons your tank holds (probably 12 if it's the same as a G60). My MFA shows about 3-5 MPG more than I actually get.

[flusted 0]

Are you doin long journeys? I get about 10-15mpg on my mfa and i only do short journeys and never get into 5th gear

[White2505 0]

been running it for about 4 weeks now. most of the journeys are about 12miles each way in duration (to and from work).

The car gets warmed up relatively quickly and its a country road run with plenty of bends :)))))

 

My mfa is already goosed so I'm going of full tank to empty and miles covered. over 4 tanks now I've averaged no more than about 20mpg

 

fuel has to be going somewhere!

[quicksilver 0]

Heavy right foot :)

[White2505 0]

Not really, being a country road I regularly get stuck behind stuff and averege 35 mph for the entire journey. I do occassionally hit the loud pedal but not often enough to drop the fuel consumption that much.

 

Its definately using more fuel than what I would consider average BUT the plugs are not showing any signs of over fueling. I have to say I'm struggling somewhat with whats up.

[Tristan 0]

I have a G60 engine on my car... when the temperature outside is aprox. below 5 degrees C then it's eatin' a lot...like 15-16 mpg... when it's higher like 21-22 mpg. This is driving in the city. What could be wrong?

[Dougalo 0]

my valver is pretty bad too. I'm early 20's MPG and i don't drive particularly fast (mostly cos i can't afford the petrol!) :?

[OK VR6 0]

I get about 25 on my VR. REset the MFA by holding button left for a few seconds, then check, no way 20mpg

[White2505 0]

okvr6, the mfa is at best inaccurate and mine is goosed anyway so no reliable figures at all from it, my mpg figures come from the mechanically derived mileage travelled on the odometer and the actual fuel consumption full tank to re-fill.

I KNOW it's only doing about 20mpg what I can't work out is why? (sigh)

[tonertron 0]

okvr6, the mfa is at best inaccurate and mine is goosed anyway so no reliable figures at all from it, my mpg figures come from the mechanically derived mileage travelled on the odometer and the actual fuel consumption full tank to re-fill.

I KNOW it's only doing about 20mpg what I can't work out is why? (sigh)

 

 

I'm with you there!!! I've got a 1.8 16v myself, and was actually about to start this very sort of thread.........

 

 

.....my fuel consumption has gone through the roof in this cold weather!! As an example. I used to average 27mpg ish, but am lucky if I get much above 20. And when it's on the off from cold, I can average as low as 2mpg for the first 500m. If I owned an enormous V8, fair enough.....but really!

 

 

Need to carry out some checks.

[OK VR6 0]

what fuel are u using, try optimax to see...

[White2505 0]

tried shell, tried bp, tried supermarket, tired unleaded, tried super unleaded.

little difference if any unfortunately