GolfGTIforum.co.uk
Model specific boards => Golf mk5 => Topic started by: golfmk4owner on 10 November 2012, 19:08
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Hi guys. I have checked loads of mpg threads, but my question is a bit different in the way that i've got some different facts to play with. I'm getting so annoyed at my findings that i've decided to be very sarcastic in order to humour myself to avoid driving off a cliff.
My dilemma: I want a mk5 GTI but am unsure how much extra fuel will cost me. I'm getting a bit more annoyed because people say "drive a tdi how you want and still get 50mpg". Well, that's what i thought but look at this...
Here's where it gets interesting. People say they can get 300 miles to a tank in a GTI. I only get 400ish in my GT TDI (140). Bare in mind by "full tank" i mean until the fuel light comes on.
But check this out...
My last fillup I reset my trip and mpg stats. My light came on at 408 miles. Now after checking my handbook it says when the light comes on there is 7 litres of fuel left. So, 55 litre tank minus the 7 litres left means i used 48 litres of diesel.
48 litres is 10.6 gallons (48/4.5 = 10.6)
this equals 38mpg (408/10.6 = 38.4)
BUT here's the part that really annoys me... My display readout said that for that tank of fuel my AVERAGE was 54MPG! As you can clearly see, i just worked out my average, and no way was it near that! Can it really be that inaccurate? Because i've just PROVED my mpg.
So i'm thinking a few things... What should a GT TDI get, on average, with mixed driving, to the light?
Secondly, if mine is very low, what might cause this?
But mostly, i'm thinking if this is what i can expect, have i got much to lose by going to a GTI?
Your thoughts please, and if you're going to give me figures, please don't give me figures from your computer readout, because frankly it's a load of sh!te. GTI miles from full to light would be appreciated!
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What sort of journeys are you doing?? Short, stop start journeys and diesels will struggle to get decent MPG
If its mainly motorway then id check your tracking and tyre pressures to start with. Then lok at the engine side of things. The biggest culprit is the MAF sensor. Equally if your car has done a highish mileage id clean out your EGR valve
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Well on that particular tank i did a fair bit (about half) of motorway driving! Why do diesels struggle for mpg in cities then?
But more to the point, even if i can get better by cleaning egr etc, why is my computer still saying 54mpg?! Absolutely nowhere near!
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The best way to be accurate with a MPG check is use the trip computer for the mileage only and reset it every time you fill up. Keep the receipt and check the mileage against the fuel you have just put in to top it back up again. Simples.
With a Modified Golf R - 1500kg and AWD, I don't look at the miles per gallon as it would make me wince - I'm out for Smiles per gallon :cool:
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Diesels struggle as they take longer to warm up and thus are less efficient until they do so
A 140 should see an easy 450+ miles to a tank :undecided:
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As said in previous threads I used to get 300+ but I never ran it from full to empty light. That's mixed driving.
In the new un then I get between 240-270 but again I'm having fun and I do think the DSG box makes a difference. If you are worried about fuel and do motorway driving I'd personally stay with the TDI. Depends on why YOU want one...as Hurdy said Smiles per Tank
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The best way to be accurate with a MPG check is use the trip computer for the mileage only and reset it every time you fill up. Keep the receipt and check the mileage against the fuel you have just put in to top it back up again. Simples.
As i said in my post, thats exactly what i did. It worked out at 38mpg. It's all very well saying you wont get as good until theyre warm etc, but even so that's nowhere near what people say they get at a minimum, and AGAIN why is the computer telling me that that tankfull averaged 54 when i workout it out and proved it was 38?
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jesus, I get more than that in my lardy vectra cdti, and I rarely get to see 6th gear on my daily commute :shocked:
did managed 72mpg on the way to Germany though :smug:
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jesus, I get more than that in my lardy vectra cdti, and I rarely get to see 6th gear on my daily commute :shocked:
did managed 72mpg on the way to Germany though :smug:
Lol. But was any of that calculated mileage though mate? Because to be honest now, any figure that anybody tells me they get I wont believe unless it's calculated. Those computer readouts are utter sh*t i have learned.
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i have kept a comprehensive record on a spreadsheet :nerd: since i owned the car. over 22k
Always fill it up, then reset, and record it. just dont work out how many gallons you have used, then how much you have spent on fuel :cry:
worst tank full was 41.8mpg
best was 57.1 but that included some spirited driving in germany after a long slow drag down there :wink:
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Well frankly that's how a diesel should be!
Anyone got any thoughts then?
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There are numerous reasons why it will be out by a certain percentage, especially in the colder months.
There are all kinds of things to do with the fuel itself, waxing points, specific density at differing temperatures, efficiency of the fuel filter, fuel pump etc.
The other thing of course is that these MPG readouts are more of a convenience for us as drivers, and the ECU is only measuring the things it has been told to. It gathers information from things like pulse width of injection, fuel flow FROM tank (remember that a lot of fuel in summer months gets sent back to tank), engine load, and road speed. What is worth mentioning is that on the live display as soon as the throttle is released the live MPG goes out of range as the engine does not pump fuel as it uses inertia from the wheels/flywheel to maintain the spinning of the engine. This is logged by the ECU which will artificially inflate your MPG figure of course. I found that going down certain roads around me I could ramp my live MPG average to 100MPG+ due to going down hills with no throttle.
I think it is safe to say that as winter approaches you can utterly disregard the readout from the computer as the log points are not representative of what you drive, I.E. it could miss a short trip to the shops, but would update numerous times on a long motorway drive.
There is of course the issue of active regen if you have a DPF.
HTH's.
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That's an interesting point. So basically, from what i've learned and experienced myself, my conclusion is that the mpg computer may as well not exist. I would expect a degree of error, but if its there "as a reference" but the reference is nowhere near then it's a waste of time. Think im gonna clean the maf, change temp sensor and give the egr a clean too, then see if that gives me near 500 miles to tank. If not, i might jump on the diesel hating bandwagon.
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It's worth having as it gives you a ball park figure. Including percentage tolerance/error which increases in winter.
However, I would look more carefully at yours before going mad about the MPG computer, as only managing ~400miles to a full tank is pish. My 130 Passat estate does a minimum of 500 to a tank and is only 55 litres like yours but has a bit more bulk to carry around. I do drive like a grandad in the mornings though as I'm too sleepy to be bothered with driving avec spirit.
Thats mostly ~10miles each way to work, no motorways or A roads either. A couple of reasonable down hills though.
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Yes i agree, but 54 compared to 38 is not a ball park figure... it is an optimistic near paper figure plucked out of thin air, therefore useless.
Defo going to investigate and if things don't improve, the car is gone.
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I will assume that the MPG read out you were going from was from position 1 on the switch and not position 2. 1 is that trips MPG and 2 is an average over extended time (unless you cleared that as well when resetting the MFD)
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It was off number 2, which i reset when i filled my tank so i could see what i had over that tank full of fuel. So yeh it definately told me 54 for that tankfull!
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Dont clean the MAF - doing so generally shortens its life span considerably. Clean the EGR valve, get the tracking checked and make sure your tyres have a decent amount of tread and the correct tyre pressures
However with winter setting in expect your MPG to drop unless you fit smaller, lighter wheels like I have done and continue to enjoy the same level of MPG :smug:
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I easily get 600+ miles per tank in my GT TDI 140. 200 miles of that a week is motorways, then weekend miles which is variable driving.
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continue to enjoy the same level of MPG :smug:
I'm not enjoying my MPG.... its terrible for a diesel. That's my point.
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continue to enjoy the same level of MPG :smug:
I'm not enjoying my MPG.... its terrible for a diesel. That's my point.
And im trying to give you suggestions to fix it :kiss:
Find someone local to you who has VAGCOM and give it the once over and a logging session :nerd:
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Yep which i appreciate :wink:
My cousin did scan it actually not long ago and all that came up was 2 glow plugs, but ill give it another scan prior to doing a few things. Its due a winter service now anyway.
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To be averaging that low an mpg is ridiculous in a TDI, even with 'town driving' and short journeys. Everyone is telling you they're getting far higher figures, with the same or similar engines and you're telling everyone you've calculated your own mpg. So that would insinuate to me (and others judging by their posts) that is something amiss.
Just as a point of reference I own a MKV Gti and every time I fill the tank up I reset the 'trip computer' and at the end of every tank (well mostly every tank :wink:) I calculate my mpg and see what the average is. If I have done predominantly town driving and short journeys, including the odd obscene five minutes, then I usually see about 320-330 miles from a tank which is an average of 27.3mpg. On motorway journeys I have achieved anywhere between 400-420 miles from a tank, using a very light right foot and driving at a constant 70/80mph, which is an average of 33.9mpg.
What the mpg reads on short journeys at the end of a tank is irrelevant, because every time I stop and start the car the 'trip' resets itself. So in essence I could drive like a looney for a whole tank and then do one 'grandad' like drive at the end of the tank and the 'trip' at the end of that drive would read the last mpg figure (which could be as high 34.5mpg) and yet I may have only realised 290 miles from the full tank, meaning the true mpg would be 23.9mpg.
Whereas if I complete a continuous journey then the 'trip' never gets reset, so I can see if the 'trip' figure is realistic. From experience in most cases I can tell you that it is, for example after completing a recent very long motorway journey from Truro to Canterbury (330 miles) the 'trip' said I averaged 30.9mpg. I had used 49 litres during the journey, equating to an actual average of 30.6mpg. So 0.3mpg difference between the 'trip' figure and the calculated figure is pretty darn close in my opinion.
I don't know whether or not GTI 'trips' are different to TDI 'trips'. But I doubt that they are that dissimilar. :wink:
:smiley:
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Yep which i appreciate :wink:
My cousin did scan it actually not long ago and all that came up was 2 glow plugs, but ill give it another scan prior to doing a few things. Its due a winter service now anyway.
Worth changing them before the cold really sets in as it will struggle to start otherwise
You to need to log the MAF and Boost to help give you an idea of whats happening :smiley:
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To be averaging that low an mpg is ridiculous in a TDI, even with 'town driving' and short journeys. Everyone is telling you they're getting far higher figures, with the same or similar engines and you're telling everyone you've calculated your own mpg. So that would insinuate to me (and others judging by their posts) that is something amiss.
Just as a point of reference I own a MKV Gti and every time I fill the tank up I reset the 'trip computer' and at the end of every tank (well mostly every tank :wink:) I calculate my mpg and see what the average is. If I have done predominantly town driving and short journeys, including the odd obscene five minutes, then I usually see about 320-330 miles from a tank which is an average of 27.3mpg. On motorway journeys I have achieved anywhere between 400-420 miles from a tank, using a very light right foot and driving at a constant 70/80mph, which is an average of 33.9mpg.
What the mpg reads on short journeys at the end of a tank is irrelevant, because every time I stop and start the car the 'trip' resets itself. So in essence I could drive like a looney for a whole tank and then do one 'grandad' like drive at the end of the tank and the 'trip' at the end of that drive would read the last mpg figure (which could be as high 34.5mpg) and yet I may have only realised 290 miles from the full tank, meaning the true mpg would be 23.9mpg.
Whereas if I complete a continuous journey then the 'trip' never gets reset, so I can see if the 'trip' figure is realistic. From experience in most cases I can tell you that it is, for example after completing a recent very long motorway journey from Truro to Canterbury (330 miles) the 'trip' said I averaged 30.9mpg. I had used 49 litres during the journey, equating to an actual average of 30.6mpg. So 0.3mpg difference between the 'trip' figure and the calculated figure is pretty darn close in my opinion.
I don't know whether or not GTI 'trips' are different to TDI 'trips'. But I doubt that they are that dissimilar. :wink:
:smiley:
Mate that is the single journey trip... if you press select/reset once, it will take you to trip number 2, which is continuous, so you can reset it each time you fill the tank and it wont reset until you reset it manually...
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are we all missing something here he has a, "R-tech remap. 175bhp."
surely that doesn't help MPG?
also its a 10 year old car, its never going to be as efficient as when it rolled out the factory, how many miles are on it?
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are we all missing something here he has a, "R-tech remap. 175bhp."
surely that doesn't help MPG?
also its a 10 year old car, its never going to be as efficient as when it rolled out the factory, how many miles are on it?
Mate that was my last car lol, I've actually got a 2005 GT TDI 140, all standard
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are we all missing something here he has a, "R-tech remap. 175bhp."
surely that doesn't help MPG?
also its a 10 year old car, its never going to be as efficient as when it rolled out the factory, how many miles are on it?
Mate that was my last car lol, I've actually got a 2005 GT TDI 140, all standard
What engine was in your last car?
Remap can help improve MPG :wink: My Audi was doing 42-45mpg prior to the remap. Post remap it would do 45-50mpg and now with the DPF removed will do 49mpg+ all day long unless I press the go-go pedal rather hard :laugh:
The feedback I get from my customers is they all on average gain about 5mpg extra once remapped :smiley: That is of course based on a healthy car :wink:
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Remap can help improve MPG :wink: My Audi was doing 42-45mpg prior to the remap. Post remap it would do 45-50mpg and now with the DPF removed will do 49mpg+ all day long unless I press the go-go pedal rather hard :laugh:
The feedback I get from my customers is they all on average gain about 5mpg extra once remapped :smiley: That is of course based on a healthy car :wink:
Couldn't agree more. My Gti has retained the standard mpg the car should have, with an added 100bhp. So that's a gain my eyes.
Mate that is the single journey trip... if you press select/reset once, it will take you to trip number 2, which is continuous, so you can reset it each time you fill the tank and it wont reset until you reset it manually...
Okay fair enough dude, I never knew that (to be frank I'm not your 'read the manual' kinda guy :grin:), to be honest I only ever look at the 'trip' 'current mpg' and 'range'.
Staying on topic, for an overpowered Gti to achieve between 27-30mpg across all types of journeys, in comparison to your standard Tdi 140 achieving only 8-10mpg more, is not right and can't be down to driving styles surely :laugh:
I would get your car healthy, if there is indeed something wrong it, which it seems there might be and then get it remapped, you will definitely see improved fuel efficiency as Rhyso knows better than anyone. I've had two previous diesels remapped and noticed a considerable difference on both cars. :smiley:
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well done for not updating your signature and confusing the f&%k out of me.
are we all missing something here he has a, "R-tech remap. 175bhp."
surely that doesn't help MPG?
also its a 10 year old car, its never going to be as efficient as when it rolled out the factory, how many miles are on it?
Mate that was my last car lol, I've actually got a 2005 GT TDI 140, all standard
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Well done for being one of those people who gets arsey over a forum post. My suggestion if you feel like throwing your weight around would be to get from behind you keyboard, learn how to bench press and then join maybe an MMA club, or maybe the army and make use of your obvious dominance.
I'm so, so sorry I forgot to update my so important signature. I can understand how that must have been a vital mistake on my part, because it may have made you look slightly less macho when my post stated i had a GT TDI 140 at the beginning. This may have proved that your memory was lacking or that your ability to read was not so great. For that I am truly sorry, although still grateful that you were man enough to congratulate me - many thanks for that.
Such a shame that I used this forum again after a while and yet there had to be one. Looks like I will leave the forum alone again then. It's a sad reality that wherever people come together, whether it be a forum or club, these "chip on their shoulder" characters are always evident.
Cheers for input guys, but looks like I'll sort it out myself with trial and error, because once again humanity just reminded me to give it a wide birth. So much for evolution hey.
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I think it might have been a joke :grin:
Don't worry I'm a c unt like this all the time. Ask anyone?
:smiley:
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Calm down; its only the internet :kiss:
Are you based in Cardiff? If you get stuck I may be able to help you out...........
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Where based in ely, bud we are currently cleaning out the egr etc and will post our findings :)
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Oh dear oh dear, some people cant take a joke, I was joking!!!
Calm down dear, its only a diesel!
:laugh:
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Oh dear oh dear, some people cant take a joke, I was joking!!!
Calm down dear, its only a diesel!
:laugh:
In the voice of Michael Winner :laugh:
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http://www.youtube.com/watch?v=NqtU3FMAENo
:evil:
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i get 31mpg in my ed30... should be seeing much more in a 140GTTDI.
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Well done for being one of those people who gets arsey over a forum post. My suggestion if you feel like throwing your weight around would be to get from behind you keyboard, learn how to bench press and then join maybe an MMA club, or maybe the army and make use of your obvious dominance.
I'm so, so sorry I forgot to update my so important signature. I can understand how that must have been a vital mistake on my part, because it may have made you look slightly less macho when my post stated i had a GT TDI 140 at the beginning. This may have proved that your memory was lacking or that your ability to read was not so great. For that I am truly sorry, although still grateful that you were man enough to congratulate me - many thanks for that.
Such a shame that I used this forum again after a while and yet there had to be one. Looks like I will leave the forum alone again then. It's a sad reality that wherever people come together, whether it be a forum or club, these "chip on their shoulder" characters are always evident.
Cheers for input guys, but looks like I'll sort it out myself with trial and error, because once again humanity just reminded me to give it a wide birth. So much for evolution hey.
jesus h christ :shocked:
Someone was tired . . . . . :whistle:
PS, just left the RAF after 24 years :wink:
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http://www.youtube.com/watch?v=NqtU3FMAENo
:evil:
Haha! That bass drop is as dirty as fingering your sister and finding your dad's wedding ring inside :wink:
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are we all missing something here he has a, "R-tech remap. 175bhp."
surely that doesn't help MPG?
also its a 10 year old car, its never going to be as efficient as when it rolled out the factory, how many miles are on it?
My 10 year old remapped TDI 150 always gives 50+mpg and quite often 56mpg over a tank and its got 185k on the clock now :tongue:
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are we all missing something here he has a, "R-tech remap. 175bhp."
surely that doesn't help MPG?
also its a 10 year old car, its never going to be as efficient as when it rolled out the factory, how many miles are on it?
My 10 year old remapped TDI 150 always gives 50+mpg and quite often 56mpg over a tank and its got 185k on the clock now :tongue:
but not much of it is orignal :laugh:
:kiss:
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About the same as your car... :tongue: :kiss:
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About the same as your car... :tongue: :kiss:
my cams are original, as is the turbo :kiss:
for now :whistle: