MPG Comparison/Observations

Just done Manchester to Inverness and back again, desperately trying to get 60mpg out of my recently purchased 1.4tdi75.
Car: 02 1.4tdi 75 no re-map, Pirelli P6000 15's all at 36psi, 116k miles, all long life services with the last one by Skipton Autos inc fuel filter 3k miles ago. No DIS but all tanks done brim to brim and then data inputted into RoadTripLE (free, very good) for iphone.
Manchester commuting pre service: 48-49mpg, 80% of a full tank at sub-30mph commuting through roadworks.
Manchester commuting post service: 51-54mpg, 80% of a full tank at sub-30mph commuting through roadworks.
Manchester to Inverness and back: 3 tanks: 58.62mpg, 59.71mpg, 59.21 mpg, all with 2 adults, 2 nippers and a car full of camping gear. All at coma-inducingly low speeds, very very light throttle position etc etc to try to crack 60mpg, damn it, so close!
 
russellbridge said:
Just done Manchester to Inverness and back again, desperately trying to get 60mpg out of my recently purchased 1.4tdi75.
Car: 02 1.4tdi 75 no re-map, Pirelli P6000 15's all at 36psi, 116k miles, all long life services with the last one by Skipton Autos inc fuel filter 3k miles ago. No DIS but all tanks done brim to brim and then data inputted into RoadTripLE (free, very good) for iphone.
Manchester commuting pre service: 48-49mpg, 80% of a full tank at sub-30mph commuting through roadworks.
Manchester commuting post service: 51-54mpg, 80% of a full tank at sub-30mph commuting through roadworks.
Manchester to Inverness and back: 3 tanks: 58.62mpg, 59.71mpg, 59.21 mpg, all with 2 adults, 2 nippers and a car full of camping gear. All at coma-inducingly low speeds, very very light throttle position etc etc to try to crack 60mpg, damn it, so close!
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Couple of things to try -
Use a diesel fuel injection system cleaning additive. Redex worked for me but it took several tankfuls to see any benefit.
Try cleaning the MAF sensor using this tip from Diesel Car. After a decent run and with the engine up to temp, idle the car for a minute then rev it to 2000 rpm and hold steay for 60 sec then switch off. Supposedly this puts the MAF into 'cleaning mode' and burns all the residue off the sensor 'hot wire'.

On a non-related topic, with a car of this age and mileage I'd recommend you have the oil changed every year / 10,000 miles

Cheers Spike
 
spike said:
Try cleaning the MAF sensor using this tip from Diesel Car. After a decent run and with the engine up to temp, idle the car for a minute then rev it to 2000 rpm and hold steay for 60 sec then switch off. Supposedly this puts the MAF into 'cleaning mode' and burns all the residue off the sensor 'hot wire'.



Cheers Spike
Click to expand...

Hi Spike do you turn it off while still holding at 2K or release then turn off ?????

Phil
 
spike said:
Couple of things to try -
Use a diesel fuel injection system cleaning additive. Redex worked for me but it took several tankfuls to see any benefit.
Try cleaning the MAF sensor using this tip from Diesel Car. After a decent run and with the engine up to temp, idle the car for a minute then rev it to 2000 rpm and hold steay for 60 sec then switch off. Supposedly this puts the MAF into 'cleaning mode' and burns all the residue off the sensor 'hot wire'.

On a non-related topic, with a car of this age and mileage I'd recommend you have the oil changed every year / 10,000 miles

Cheers Spike
Click to expand...

Thanks Spike
Will try Redex and the MAF sensor cleaning proceedure described above. Failing that I'll clean the MAF by taking it off, although I'll need to get a new set of security bits first as in my excitement at changing the headlight bulbs I went for a test drive at 1am with them still on top of the car! Not my finest hour...
You've echoed Skipton's comments re engine oil.
I did notice a very slight surging at 2200rpm in fifth on very light throttle openings, would this be a dirty MAF sensor related issue too?
 
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the grim reeper said:
Hi Spike do you turn it off while still holding at 2K or release then turn off ?????

Phil
Click to expand...

Hi Phil
Yes, thats how I did it. The reason for idling the engine first is to ensure the turbo has cooled down before runnning at 2000 rpm.
The only thing I can't work out is if the A2 MAF actually has this self cleaning mode.
The theory is sound though as fuelling is primarily controlled by the ammount of air going into the engine. If this is out by a few % then the ammount of fuel injected will be to.

Cheers Spike
 
DIS showing 60.0 mpg after 450 miles (was 60.4 until trip into town this morning) and fuel light just come on. Mixture of fastish motorway (75-80 mph), local commute, trip around Yorks Dales, @ 60% with passenger and dog, remainder solo. Expecting around 60.5 mpg when I fill up later and calculate brim to brim. Similar spec and upgrades to yours dan. Will run the MAF cleaning sequence after fill up.
 
My wife has now taken over my A2. Even before the fill up I can see the fuel gauge shoot downwards at an alarming rate.....sigh. I may have to remove the mpg from my signature in shame ;)
 
My girlfriend is the same, not being a great driver (or interested remotely in cars) she forgets to change gear and drives along in 3rd or 4th revving the engine and then wonders why her car is so poor on fuel.... I mistakenly said when I am in a position to cahnge my a2 she can have it......
 
So what do I do now to get beyond 60mpg?
Fashion some sort of flat rear floor?
Fit the 1.6TDi rear spoiler?
Drive slower? (Not really an option!)

I'm bidding on a Scan Gauge at the moment thought that might help me spot when I'm not driving as economically as I might.
 
I would say that the smoothing of the boot area would help as it does seem to be quite a big expanse that would trap air.
Im not sure what the higher spoiler would do for the cost? I know the top speed is allegedly increased but will that help economy when driving st 70mph?
All the VW bluemotions seem to have blanked grills - is this the way to go?

Im also interested in upping the mpg but i dont really want to drive around with all the seats removed every day of the week :p
 
I have been reading the fuel discussions (not all tho ) with interest. One mild but breezy evening I got onto the M20 with one gallon of diesel on board, with the climate off & windows shut I got 96 miles out of the gallon ( but nearly died of boredom driving between 40 & 50 MPH)
 
Dan b
I'm in the same position as you - whatever I do I can't get above 60mpg! However having got very very bored driving at 60 for hours on end trying to get 60mpg plus out of a tank I discovered that driving at 80-85 still gets 52-53mpg so have decided that this a much better way to spend my valuable time...(having done 340mile runs 4 times over the past three weeks with twin 2 year old's on board I can confirm that the speedier shorter trips were the more enjoyable...)
I'm trying Spike's recommendation of a prolonged dose of millers, I'll report back when I get chance to do another mind numbingly slow trip...
Also interesting to note that the A2 seems happiest sat at bang-on 70 on the motorway - this seems like a happy blend of road noise, engine noise and available 'poke', although this does mean that you're constantly in and out of inside lane and going slower than the majority of the middle / outside lane traffic. My old Audi TT 185 seemed happiest at 83 (quite short gearing in fifth), my old Skoda Octavia VRS happiest at 90, and my boss recons his '07 AMV8 is happiest at 107!
 
Well since fitting my 17's i haven't hit the 60 mark but i have never driven to the full tank allways starts off good but then the last half/quarter i end up driving short distances

but between now and the end of the year i've got some big drives on the cars and after ADI my 16's are going back on will have a good comparason will be on the cards and i'll post on here what got

the best i had was 72mpg's and that was before all areo mods and on 16's

Cheers Phil
 
I've just filled up the car for the first time since my wife has taken over the A2.

54 mpg!

It's not a fair comparison since she nearly only does short town journeys, but for me:

best: 78 mpg
worse: 61 mpg
average: 68 mpg

So on the whole 54 mpg isn't so bad, but just not a number I'm used to seeing.
 
I do mainly town driving during the week and I get between 45 and 50 mpg.

Cant seem to get it any higher than that.

John
 
Given up measuring accurately, but these figures now seem to be the norm for me in a remapped 75 TDi on 16's x 205 with .659 5th gear:-

Town use only - 50mpg

Mix of Town & A roads - 55mpg

'A' roads only at 60mph - 65mpg (& if I really concentrate on economy 70mpg)

Motorways at between 70/80mph - 55mpg

add a heavy load and aircon and you can deduct at least 5% off the above and more in a hot climate
 
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