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actual vs mfa mpg
Posted: Wed May 02, 2012 2:29 pm
by iroberts696
Have a 1.8i scala, mfa ranges from 28 cold about town to a best of 51 after 1/2 hour of 40 to 60 with an ave of 39 for long ( 200 mile + ) motorway drives.
However logging liters in vs miles out gives 31 to 33 regardless . Have been using the 'super' unleaded timing has been set accordingly.
What are other folk getting ? presume the MFA number is ornamental as seems more affected by weather / fuel brand
Any way to make the mfa more realistic ?
Re: actual vs mfa mpg
Posted: Wed May 02, 2012 2:45 pm
by Brunty
I actually found my GTX which was standard at the time to be pretty accurate at 36.6mpg over a tank. That was a mix of driving types, but a bit more of higher speed motorway.
Re: actual vs mfa mpg
Posted: Wed May 02, 2012 5:28 pm
by ianaudia4
Both my Sciroccos return an average of 38 mpg, my mfas are pretty accurate as they record roughly the same.
Re: actual vs mfa mpg
Posted: Wed May 02, 2012 7:15 pm
by DT1
iroberts696 wrote:Have been using the 'super' unleaded timing has been set accordingly.
1.8i Scalas are set up to run 98 RON as standard, was the timing changed before to use normal unleaded?
Mine has always been fairly accurate, going by pump readings and MFA comparisons,
Re: actual vs mfa mpg
Posted: Wed May 02, 2012 10:40 pm
by shaun_89
Mine is pretty accurate aswell, i get around 410-420 miles for a tank - around £63 on v-power
MFA says between 41.4 - 44.2 normally, real world mpg is 43.7ish
Re: actual vs mfa mpg
Posted: Wed May 02, 2012 11:40 pm
by Brunty
shaun_89 wrote:Mine is pretty accurate aswell, i get around 410-420 miles for a tank - around £63 on v-power
MFA says between 41.4 - 44.2 normally, real world mpg is 43.7ish
Wow! Wish my daily golf gti got somewhere near that! 200bhp and a lardy body I suppose :(
Re: actual vs mfa mpg
Posted: Thu May 03, 2012 11:26 am
by iroberts696
Had the kjet 'tuned' for 98 ron a couple of months back when I was working in Leek, was running lean , tune made the car a bit more zippy and changed which make of petrol read highest on the mfa ( was tesco ultimate now shell vpower ) but didnt change the mpg as calculated by the andriod app.
Was regularly doing 250 mostly motorway miles Glasgow/Leek on 32 to 35 litres
( travelling south using the lower figure prevailing winds/ sunday traffic vs friday traffic )
so by that mpg would be (250 / 35) * 4.54 = 32.4 mpg
After some browsing this would appear to be in line with
http://www.fuelly.com/car/volkswagen/scirocco/1987
However would like to be closer to
shaun_89 wrote:Mine is pretty accurate aswell, i get around 410-420 miles for a tank - around £63 on v-power
MFA says between 41.4 - 44.2 normally, real world mpg is 43.7ish
unless it means sitting at 55/60 all the time ! or at least have the meter a little less optomistic
Re: actual vs mfa mpg
Posted: Thu May 03, 2012 11:44 am
by Brunty
Cool, and I actually know one of those guys!
I found that "normal" driving over a variety of speeds I only ever got 37mpg, even though my Dad in his slightly tunes Scala managed to average a decent 40 to the gallon. He didn't hang around much either. It always seemed odd that 2 so very similar cars would use such different amounts of fuel. It could be the quality of the injectors/fuel/tune/spark plugs...
Re: actual vs mfa mpg
Posted: Thu May 03, 2012 4:36 pm
by shaun_89
iroberts696 wrote:
shaun_89 wrote:Mine is pretty accurate aswell, i get around 410-420 miles for a tank - around £63 on v-power
MFA says between 41.4 - 44.2 normally, real world mpg is 43.7ish
unless it means sitting at 55/60 all the time ! or at least have the meter a little less optomistic
You are correct, i sit around 58-62mph on the motorway and most of my driving is fast a-roads at 60mph.
I do mostly night driving with little traffic aswell so i just come off the accelerator in 5th when i get the right distance away from an island etc, then i dont need to brake and waste fuel.
Most people find this boring but i find it good fun, highest real world mpg ive had is 46.2mpg.
Re: actual vs mfa mpg
Posted: Thu May 03, 2012 8:27 pm
by DanH
I don't have an MFA but my 1.6 gt averages about 31.5mpg based on noting down mileage/petrol put in. Best I've ever had is 36.5 and that was changing up at 2200revs every time etc etc
Re: actual vs mfa mpg
Posted: Fri May 04, 2012 8:21 am
by ghost123uk
Brunty wrote:Cool, and I actually know one of those guys!
Is it the owner of "Lil Red" ? - if so how does he manage to get as bad as 25 MPG average :o
Just for the stats, when I had a GTX I found the MFA pretty much the same as real world calcs.
Re: actual vs mfa mpg
Posted: Fri May 04, 2012 9:37 am
by Brunty
ghost123uk wrote:
Brunty wrote:Cool, and I actually know one of those guys!
Is it the owner of "Lil Red" ?
Ha, no. The other...
Re: actual vs mfa mpg
Posted: Fri May 04, 2012 5:57 pm
by MikeH
The Kjet Roccos and the Mk2 golfs I've had have all been capable of 40+mpg on a run at 70-75mph. One of them was pretty accurate MFA wise, one of them reads about 10% optimistic. Over a tankful I tend to get 36-37 mpg with normal driving, but more if I'm cruising up the motorway to Scotland, or less if it's all town and B roads.
The way you drive is a big influence - especially throttle control and anticipation of when you will need to slow down. Tyre pressures and brake adjustment too. Just for an extreme example, I get 13 mpg on a lap of the Nurburgring in the track car (1 gallon a lap) and it does 35mpg on the motorway getting there - sitting at about 75-80mph (150bhp 2.0 8v on Megasquirt).
If you're getting low 30s mpg average in a scala then I'd do a compression test, cam timing check, pump your tyres up a couple of psi (F31/R29 ish) or just go on an advanced driving course.
Might also be the injector spray pattern isn't great, or delivery varies between injectors. All worth a look - jam jars at the ready!
Re: actual vs mfa mpg
Posted: Sat May 05, 2012 10:25 am
by jim91
Mine was same as most folk have said was around 28mpg on daily commute, sat in traffic rarely getting over 20mpg and would give about 40mpg on a motorway trip at 70mph. I tested the mfa against my own calculations a few times and was always more or less the same.
I fitted a new AAV a few months ago and mpg doesn't seem to be as good but I haven't been working it out and whilst setting clock a while back I've pushed too hard and bust the screen as ink all over it so could prob do with another one, and it might be all in my head as got golf tdi for the mrs which I've been using at times so the 60mpg on that maybe has me spoilt and thinking rocco bit harder on fuel.
Generally use ordinary unleaded altho do folks feel BP super or similar would be better?
Re: actual vs mfa mpg
Posted: Mon May 07, 2012 4:12 pm
by iroberts696
Am a bit confused by all this as.
Originally posted to see if any way to make the mfa mpg more closely match actual, whereas thread seems to have turned into how to make actual consumption match the mfa ! ( not quite the same )
Sure I appreciate that driving fast and fuelish, jumping on the accelerator/breaks while running on soft tyres reduces mpg even reducing it on the mfa .....
I can drive so the mfa reads all day in the mid to high forties or the mid to high 30s however doing the sums gives low 30s with perhaps a range of 3mpg in the actual compared to the range of 10mpg in the mfa. ( This is the second set of clocks that behaves like thus )
So I suppose that there must be some problem with my engine setup ( assuming that 40 mpg is realistic ) can anyone point me at a definitive source for that ?