1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

A3 2.0TDI low poor sh*t MPG.. driving me crazy some 1help!!

Discussion in 'A3/S3/Sportback (8P Chassis)' started by AntonTDI, Oct 19, 2011.

  1. AntonTDI
    Offline

    AntonTDI Member

    Joined:
    Feb 23, 2011
    Messages:
    44
    Likes Received:
    0
    [Oct 19, 2011]
    Hi all,

    I got a 2006 A3 2.0TDi 140 sport, 145k on the clock.

    Got really bad mpg like 28 on average, so a friend reccomended to change the fuel filter, was a big sucsess 48+mpg!

    Then the seals go on(lots of whislte) the turbo cooling system that leads to the intercooler (the big pipes) so my guy changes them all!
    Also changed the 2 front tyres and now I'm getting. 33mpg!!
    50pound of fshell fuel save gets me 3/4's of a tank wat give me 300 miles..

    Witch in reailty gets you no where!

    Tyres are in flated all round to 34psi! New diesel filter a month ago, all turbo intercooler pipes are sealed well! New tyres, good quality fuel so what could it be!

    One of those things that you just think 'nightmare' and this is one of them!

    All your help would be apprchiated!

    Sorry for ne mistakes posting off my bb X0

    Thanks
    #1
  2. Ads

    Ads

    [Dec 27, 2014]

  3. vw754
    Offline

    vw754 vorsprung Durch Technik

    Joined:
    Nov 4, 2006
    Messages:
    2,071
    Likes Received:
    35
    [Oct 19, 2011]
    have you changed the coolant sensor? do you have access to vcds(vag-com)?
    #2
  4. Graham89
    Offline

    Graham89 Derv Perv

    Joined:
    Jul 19, 2011
    Messages:
    310
    Likes Received:
    4
    [Oct 19, 2011]
    Coolant temp sensor? Might be reading to low making your ECU throw more fuel in than needed.
    #3
  5. AntonTDI
    Offline

    AntonTDI Member

    Joined:
    Feb 23, 2011
    Messages:
    44
    Likes Received:
    0
    [Oct 19, 2011]
    Hey guys thanks for the reply,

    Yea I got access to vag-com, what should I tell my guy to check? Never changed the coolant temp sensor! U guys think its this? Is that a common thing?

    Plus I forgot to mention before it had a new engine @ audi 20thousand miles ago, frm previous owner! So the mileageshould nt really affect it..

    Gettin sick of driving like a granny! Soon as I boot it bye bye diesel :(
    #4
  6. TimG
    Offline

    TimG Active Member

    Joined:
    Feb 21, 2004
    Messages:
    941
    Likes Received:
    42
    [Oct 19, 2011]
    Am I correct in thinking there are 2 of these sensors on these engines?
    #5
  7. AntonTDI
    Offline

    AntonTDI Member

    Joined:
    Feb 23, 2011
    Messages:
    44
    Likes Received:
    0
    [Oct 19, 2011]
    Hey guys thanks for the swift reply, I got access to vag com what should I tell my guy to look for on it? Will I be able to no if I need to change the sensor from the vag com?

    Also is there two sensors or just 1?

    Is it a known faulty or common problem with these sensors?

    Getting sick of driving like a granny now! When I boot it its bye bye diesel :(
    #6
  8. TimG
    Offline

    TimG Active Member

    Joined:
    Feb 21, 2004
    Messages:
    941
    Likes Received:
    42
    [Oct 20, 2011]
    They are known to break. Ive replaced one of pretty much every VAG car Ive had, and need to do mine now as it threw up a fault a few months back (not quite got round to sorting it!). When you scan VAGCOM will register an error relating directly to the temp sender if its faulty.

    DOes your temp needle sit on 90 degrees. Thermostat might be fooked if not.
    #7
  9. AntonTDI
    Offline

    AntonTDI Member

    Joined:
    Feb 23, 2011
    Messages:
    44
    Likes Received:
    0
    [Oct 20, 2011]
    Hey mate, yea it does sit on the 90! Bang on half way..

    What does this eleminate now?
    #8
  10. Ash187
    Offline

    Ash187 Audi-Retrofits.co.uk Site Sponsor

    Joined:
    Mar 12, 2009
    Messages:
    6,843
    Likes Received:
    483
    [Oct 20, 2011]
    this sounds silly but a full fluid and filter service does wonders. i was experiencing lower MPG and lag on my car and was ignorign the service light for a couple weeks but then the lag progressed to rough acceleration. did an oil change, oil filter, fuel filter, air filter, etc.. and now car is puling like a train again and average MPG is back to where i am used to seeing it... 55 - 60 MPG
    #9
  11. 1inchpunch
    Offline

    1inchpunch Member

    Joined:
    Apr 14, 2011
    Messages:
    450
    Likes Received:
    15
    [Oct 20, 2011]
    Does sound like a coolant temperature problem. I'm not that up on Audis but it was a common fault on BMWs with the 320d often returning MPG in the low 20s due to 1 or both of the sensors being faulty. The tell tale sign with them was that the car felt fine in every way until you noticed the fuel gauge rapidly moving to the left.
    #10
  12. The Engineer
    Offline

    The Engineer Member

    Joined:
    Apr 25, 2011
    Messages:
    355
    Likes Received:
    21
    [Oct 20, 2011]
    I get around 200 miles to £40 in my mapped 2.0 TDI. was quite content with that.

    What is the average people get from the 140 TDI? :huh:
    #11
  13. TimG
    Offline

    TimG Active Member

    Joined:
    Feb 21, 2004
    Messages:
    941
    Likes Received:
    42
    [Oct 20, 2011]
    Thats about 32 MPG which is appalling!

    I often put in 15 litres (about £21) and I get 140-160 miles. Thats around 43-48 MPG.
    #12
  14. vw754
    Offline

    vw754 vorsprung Durch Technik

    Joined:
    Nov 4, 2006
    Messages:
    2,071
    Likes Received:
    35
    [Oct 20, 2011]
    i get 60-65 on a tenner.
    #13
  15. marty1
    Offline

    marty1 New Member

    Joined:
    Oct 5, 2011
    Messages:
    9
    Likes Received:
    0
    [Oct 20, 2011]
    On a recent 200 mile trip it took £25 to fill the car to the rim at 139 per litre, think that worked out around 50 mpg. On mixed i get 40 mpg and using the car only to get to work and home (9 mile round trip) , so the engine never gets a chance to warm up i get 33 mpg, that's cruising around 80 mph for 7 miles of that. The car has been remapped but to around 180 bhp but that only comes into effect if i floor it, which i don't very often...
    Thought that was around average for a 140 Tdi ??? :unsure:
    #14
  16. The Engineer
    Offline

    The Engineer Member

    Joined:
    Apr 25, 2011
    Messages:
    355
    Likes Received:
    21
    [Oct 20, 2011]
    Pretty much the same deal with me, got a mapped 140 TDI.

    My commute to work is 5 mins tops as I live very close to work, lucky really.
    Suppose the car never really warms up.

    Took it up the motorway last weekend and got 60mpg on the DIS, Was very happy with that :rock:
    I think it's the type of driving I do that determines the fuel usage. Our diesels are best for long journeys.
    #15
  17. Ash187
    Offline

    Ash187 Audi-Retrofits.co.uk Site Sponsor

    Joined:
    Mar 12, 2009
    Messages:
    6,843
    Likes Received:
    483
    [Oct 20, 2011]
    A full tank gets me about 500-550miles, thats a mix of motorway, town and heavy footed driving :racer:
    #16
  18. ryanstewart9
    Offline

    ryanstewart9 Member

    Joined:
    Sep 5, 2009
    Messages:
    455
    Likes Received:
    7
    [Oct 21, 2011]
    I get around 500-550 miles to a full tank & that's mainly motorway driving on a standard 140TDi (45mile round trip to work).

    Trip says it averages mid 40's MPG.
    #17
  19. Beans
    Offline

    Beans Member

    Joined:
    Jan 27, 2012
    Messages:
    81
    Likes Received:
    0
    [Apr 9, 2012]
    I've just got an 06 TDI 140 (PD engine), and my first full tank I got 42mpg - approx 500miles. I always fill the tank to the brim, and I zero the trip computer so when I fill next time I can work out the true MPG.

    I'm hoping I get a lot better than that, although I've only had the car 10days (done 700miles so far in it). My computer said I had 530miles on a completely full tank.

    Also, when does your turbo kick in? Mine seems to be 2,500revs upwards which is higher than usual for a diesel.
    #18
  20. NHN
    Offline

    NHN Retrofitter - Audi - VW - Skoda - Seat Site Sponsor VCDS Map User

    Joined:
    Jan 14, 2008
    Messages:
    27,511
    Likes Received:
    1,274
    [Apr 9, 2012]
    Depends on your driving styles & locations, motorway will be higher, but city/towns will drop, 42mpg isnt too bad, more info needed.

    530 on full tank isnt bad at all tbh.

    2-2.5 seems ok for turbo, but only way to be sure if from diagnostics as the needle isnt perfectly accurate is it, if you have sticking vanes then it may be a little lazy, only 1 way to check tbh is by removing, but some logs & comparisons will advise of any issues, using say vcds.
    #19
  21. The Governor
    Offline

    The Governor Active Member

    Joined:
    Mar 21, 2012
    Messages:
    440
    Likes Received:
    65
    [Apr 10, 2012]
    I've only had mine a week, Tdi 170 Quattro but my first brim to brim calculated mpg was 42. It has about 2500 miles on it so it might loosen up a bit as time goes by.

    That was generally A road/motorway with a few short runs mixed in.

    Obviously early days but just thought I'd post for comparisons sake :)
    #20
  22. paultaylor
    Offline

    paultaylor Member

    Joined:
    Aug 30, 2003
    Messages:
    294
    Likes Received:
    4
    [Apr 10, 2012]
    I have a 07 170 TDI DSG with 40k miles and only get 330 miles for a full tank!

    It's all short urban journeys with the odd run on the motorway.

    It's been serviced for long life service 2000 miles ago and runs smooth(injectors change made it even smoother)

    Any thoughts??

    thanks
    #21
  23. mjr901
    Offline

    mjr901 Parts Manager - (Main Dealer)

    Joined:
    Nov 24, 2011
    Messages:
    2,863
    Likes Received:
    534
    [Apr 10, 2012]
    :scared2: thats S3 territory!! should be double that!
    #22
  24. paultaylor
    Offline

    paultaylor Member

    Joined:
    Aug 30, 2003
    Messages:
    294
    Likes Received:
    4
    [Apr 11, 2012]
    Has anyone any thoughts on what I should be checking in order to improve it?

    tyre pressures?

    anything on VCDS?

    thanks
    #23
  25. mjr901
    Offline

    mjr901 Parts Manager - (Main Dealer)

    Joined:
    Nov 24, 2011
    Messages:
    2,863
    Likes Received:
    534
    [Apr 11, 2012]
    i think I'd be checking to see if somebody has swapped your engine over in the night?! ;)

    on a serious note I guess I'd be checking fuel filter, perhaps MAF readings etc.

    try remapping it. might improve things. it did on mine.
    #24
  26. Ash187
    Offline

    Ash187 Audi-Retrofits.co.uk Site Sponsor

    Joined:
    Mar 12, 2009
    Messages:
    6,843
    Likes Received:
    483
    [Apr 11, 2012]
    When was the last time it had a full service? i saw a nice gain when i changed my fuel filter and oil filters on my last full service.
    also i dont know how you drive but i have been driving at a max speed of 75mph on motorways and in general town driving i try not to rev it too much when pulling away from lights... try not to use the brakes too much so drive a little more slower and leave more space between cars so that you can just lift your foot off the accelerator to slow down?
    I know thats not entirely helpful but i have found that those little changes have improved my MPG from 54-55 to 60-62
    #25
  27. c_w
    Offline

    c_w Well-Known Member

    Joined:
    Feb 23, 2010
    Messages:
    1,058
    Likes Received:
    62
    [Apr 11, 2012]
    450-500 should be easy with mixed driving with the diesels, to get 600+ means mostly motorway steady speeds.
    #26
    Roady likes this.
  28. paultaylor
    Offline

    paultaylor Member

    Joined:
    Aug 30, 2003
    Messages:
    294
    Likes Received:
    4
    [Apr 11, 2012]

    It had a full service at 37.5k miles and it's on 40k now, the sevices was oils, filter air etc it also had DSG oil and filter done.

    As I do short trips where it doesn't have a chance to get up to full temp could the DPF be getting blocked and lead to higher consumption?

    The DPF regen light has come on once so I stayed on motorway as described in the manual until it went out
    #27
  29. paultaylor
    Offline

    paultaylor Member

    Joined:
    Aug 30, 2003
    Messages:
    294
    Likes Received:
    4
    [Apr 11, 2012]
    I've read running out fuel is bad as the system need to be bled but I've never done that.

    Is running it low until the warning light comes on or ten miles past that point bad for a diesel engine?
    #28
  30. a3sline_nottingham
    Offline

    a3sline_nottingham Member

    Joined:
    Mar 21, 2012
    Messages:
    64
    Likes Received:
    0
    [Apr 12, 2012]
    ive got a Sline 2.0Ltr TFsi pertrol and my fuel consuption is shocking - at todays prices i fill up £20 and get 100 miles so on a full tank of about £70-£75 im getting around 350ish

    Is that bad - the car has clocked 100k so what do you reckon i should do to increase MPG - fluid and filter changes ??
    #29
  31. paultaylor
    Offline

    paultaylor Member

    Joined:
    Aug 30, 2003
    Messages:
    294
    Likes Received:
    4
    [Apr 12, 2012]
    What kind of driving are you doing?
    #30
  32. c_w
    Offline

    c_w Well-Known Member

    Joined:
    Feb 23, 2010
    Messages:
    1,058
    Likes Received:
    62
    [Apr 12, 2012]
    Cost of the fuel is irrelevant, it just sounds worse mile/pound than ever these days!! 350miles on a tank isn't bad, that's about 35mpg assuming you don't run it dry (ie 1 gallon usually always left on an "empty" tank).
    #31
  33. a3sline_nottingham
    Offline

    a3sline_nottingham Member

    Joined:
    Mar 21, 2012
    Messages:
    64
    Likes Received:
    0
    [Apr 12, 2012]
    i do communting 14 mile a day (7 to work and 7 back) and then a 130 mile round trip at the weekend. I never let it go all the way down, just when the display shows 30ish miles left
    #32
  34. jay6392
    Offline

    jay6392 Member

    Joined:
    Nov 27, 2011
    Messages:
    67
    Likes Received:
    2
    [Apr 12, 2012]
    I have a Audi a3 sports 140 and i this month put £80s iof performance diesel and i got about 750 miles on a full tank, Monday to Friday around trip in do 24miles and that's little back roads and dual-carriage ways doing speeds off 50 to 60 miles an hour max but by the end off the third week i have to put in an extra £20 just to see me to the end off the month, i have no lights on my dash no power problems very thing is working great on the car but i feel there is something wrong still any ideas

    thanks jay
    #33
  35. The Governor
    Offline

    The Governor Active Member

    Joined:
    Mar 21, 2012
    Messages:
    440
    Likes Received:
    65
    [Apr 12, 2012]
    Hold up, you're getting 750 to a tank and you think there's something wrong? I think you need a clairvoyant dude :D
    #34
    staceface likes this.
  36. jay6392
    Offline

    jay6392 Member

    Joined:
    Nov 27, 2011
    Messages:
    67
    Likes Received:
    2
    [Apr 12, 2012]
    lol yeah but serious is there some thing wrong our is it some thing i am doing wrong driving wise
    #35
  37. SCFC_Messiah
    Offline

    SCFC_Messiah Member

    Joined:
    Mar 5, 2012
    Messages:
    278
    Likes Received:
    13
    [Apr 12, 2012]
    I've got a 2.0TDi 170 on 98K. I've been through two tank refills since buying the car now

    First tank full involved 80%+ city driving - plenty of start stop and loads of up hill driving, so not good conditions for fuel economy. I got 34MPG according to the on board computer, but in reality it worked out as 35MPG. I'm happy enough with that - the car is going on twice as powerful as my previous 2.0 turbo diesel (Peugeot), yet still managing slightly better MPG around the town

    The second tank full involved 90%+ motorway driving - mainly around the 70MPH mark, so not too heavy footed. I managed 54MPG in reality, whilst the on board computer read 55MPG. This is a good 5 or 6 MPG better than my previous car, so I'm very happy with this return


    On another note, I was told on here that the on board computer tends to over read your MPG return, so in reality you should knock a few MPG of what it tells you you're getting. But to be honest I found it almost spot on for both occassions now
    #36
  38. mike foster
    Offline

    mike foster Fossie VCDS Map User

    Joined:
    Jan 16, 2010
    Messages:
    3,967
    Likes Received:
    79
    [Apr 13, 2012]
    750 miles to a tank !!!!!!!!!!!!!!! Surely that's impossible even if you never exceed 30 mph ?? :think:
    #37
    Andy86 likes this.
  39. jay6392
    Offline

    jay6392 Member

    Joined:
    Nov 27, 2011
    Messages:
    67
    Likes Received:
    2
    [Apr 13, 2012]
    No that's what it says honiest what I will do is take photos when I fill up again on the first off the month with cost and and every thing
    #38
  40. c_w
    Offline

    c_w Well-Known Member

    Joined:
    Feb 23, 2010
    Messages:
    1,058
    Likes Received:
    62
    [Apr 13, 2012]
    750miles is doable on long journeys but you got to be mega light footed to do it over a series of shorter journies.
    #39
  41. SCFC_Messiah
    Offline

    SCFC_Messiah Member

    Joined:
    Mar 5, 2012
    Messages:
    278
    Likes Received:
    13
    [Apr 13, 2012]
    Exceeding 30 is better for fuel efficiency. I read a while back that a continued 56MPH is the best speed for an optimal MPG return. Obviously that varies for different cars and different engines, but in general that's around the best speed. It tails away VERY quickly around 70MPH and beyond though



    I don't trust that computer at all. Your best bet is to reset computer 2 and measure you're MPG over the course of a tank full. Once you've emptied the tank, let us know what the MPG return was according to computer 2. I think I'm correct in saying that 750 miles to a tank full would work out around the 60MPG mark, which I'd say is only do able in constant, very restrained motorway driving
    Last edited: Apr 13, 2012
    #40

Share This Page