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

A6 2.5 TDi Fuel econ 29 mpg ?

Discussion in 'Diesel forum' started by rich dj, Aug 8, 2006.

  1. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    i can only seem to get about 29 mpg out of my A6 2.5 TDi auto tiptronic 75000 miles is this about right?
    Some days it seems quicker than others.
    Any ideas:blink:
    #1
  2. peteA3tdi
    Offline

    peteA3tdi Member

    Joined:
    Mar 10, 2004
    Messages:
    408
    Likes Received:
    0
    its better then the 18mpg i got from my old one!! i got more from a chiped S3.
    #2
  3. topscaff
    Offline

    topscaff New Member

    Joined:
    May 4, 2006
    Messages:
    23
    Likes Received:
    0
    29 mpg does seem a little low, but i suppose it depends on a lot of variables.
    I drive a 2002 Auto 2.5 Tdi Allroad which is probably a little heavier than an A6 but i generally get 32-34 MPG. I reset the computer after every fill and my average speed per tank is approx 32MPH.

    I do approx 20% town driving, 20% Motorway and 60% getting frustrated behind all the holiday makers and "40MPH on a wide open road merchants:gun2: ".
    #3
  4. kris_tdi
    Offline

    kris_tdi Member

    Joined:
    Aug 22, 2004
    Messages:
    164
    Likes Received:
    0
    i have an a4 2.5 tdi and it seems to average around 38 mpg, mixture of town and dual carraigway. not bad considering its performance.
    #4
  5. fjtwelve
    Offline

    fjtwelve Moderator Staff Member Moderator

    Joined:
    Jan 6, 2006
    Messages:
    769
    Likes Received:
    9
    I average 33mpg from my A6 2.5tdi quattro (last 25000 miles), the chip didn't make much difference to the economy. The computer underreads by 1.5mpg against hand calcs.
    #5
  6. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    ok so i f you doing 33 mpg in a 180hp quattro which is suppost to do less mpg than my 150hp v6 i would suggest i need to do something anybody any ideas, i put some injector cleaner in 2 weeks ago and did not seem to make any difference it was the red x extra one, does anyone know if the injector cleaners you put in the chamber with a new diesel filter work ok with the audi's, a lot of garages use this to get older diesels through mot's, it gave my old 405 with 130000 miles a whole new lease of life, qicker and better fuel econ.

    Or Could it poss be sensor failing could cause probs?
    #6
  7. dummi
    Offline

    dummi smoking a6

    Joined:
    Mar 25, 2004
    Messages:
    1,210
    Likes Received:
    0
    why not vagcom it then you will know for sure if it is electronic problem or not.
    #7
  8. fjtwelve
    Offline

    fjtwelve Moderator Staff Member Moderator

    Joined:
    Jan 6, 2006
    Messages:
    769
    Likes Received:
    9
    Nearly all my driving is out of town. My DIS average is usually around 48mph. If all yours is in town that may be a factor. I notice you say its better some days than others. Have you done all the normal MAF N75 etc checks? I agree you should get it VAG COM'd . Using Shell or BP fuel may help if you aren't already doing so. At 79,000 it should be nicely run in, not suffering injector problems. I would be very surprised if it is a mechanical problem of this kind.
    #8
  9. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    "Have you done all the normal MAF N75 etc checks? I agree you should get it VAG COM'd ."
    no sorry bit new to this sorry if im going to ask a question thats prob been asked before, ok so i am going to buy a vagcom lead with my mate who has a Skoda Supurb with the same v6 2.5tdi lump there seems to be 2 different types of lead i was looking on www.ecutool.com

    VAG-COM CAN-BUS KKL USB Cable

    VAG-COM USB KKL Cable

    which one do i need ?

    mine is an A6 2.5 SE V6 TDi auto tip Year 2000
    mates is skoda supurb (the top model?forget name)2.5 TDi Auto tip year 2006

    And how do i do the checks on the MAF N75 or could you point me to a thread thats tells me
    if new MAF N75 required best place to get one from.

    My Driving is mainly out of town but some small country roads if that helps.
    #9
  10. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    i Have unpluged the MAF (after very long surf through threds) and gave the car a short drive and found it to be gutless and no power so i would say that is ok.
    now waiting for vagcom lead to give checkover for fault codes.

    And next fill up will be "Using Shell or BP fuel may help if you aren't already doing so"

    PS mates 06 Skoda will do 38-42ish only difference is that his is the higher power V6 155 or 163 not sure which one and done 60000 miles less
    #10
  11. fjtwelve
    Offline

    fjtwelve Moderator Staff Member Moderator

    Joined:
    Jan 6, 2006
    Messages:
    769
    Likes Received:
    9
    my driving is nearly all out of town too so type of driving is not a reason. mine is also quattro which theoretically does less mpg than a 2wd.
    agree your MAF sounds to be OK.
    The N75 controls boost pressure and is a control valve adjacent to the turbo, but if this has gone its normal that the performance goes not the fuel economy
    i recently read a thread where replacing the fuel filter cured several poor performance symptoms. check the air filter too, mine was completely knacked when i bought the car.
    auto box is not holding lower gears too long ? not stuck in sport mode or something?
    go to tdiclub.com, there is a massive amount of info there, and you will probably be best starting in faqs
    #11
  12. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    i looked at the air filter it looks like i need replacing getting one at the weekend to give a go, Euro parts ok? they do one for £4 and one for £8 or do i put in orig Audi?
    My lower gears do feel like sport mode, only had the car 4 weeks or so spoken to Audi they say the car will learn your driving style as the car came from city they said it would do this in town driving and it would take 500+ miles to learn me.
    have done 1500 miles but i still think it revs high before changing gear it does feel like sport mode but there is no switch..
    last few days been driving in tip mode and seems to be bringing up the mpg a bit.
    it does want to change up on hills a lot as well. I have had new gearbox oil fitted aswell as has never been done.
    also 3rd gear seems to have 2 modes like 3 and 3 and a half as if i have six gears but only 5.
    Have you seen any threads about these gear box problems problem.
    #12
  13. marmite
    Offline

    marmite Counting the Tesco Club points

    Joined:
    Jul 20, 2006
    Messages:
    1,101
    Likes Received:
    0
    I was getting that out of my Allroad 2,5tdi on a run to work 30mph then 70-80mph back to 50 mph ish on a good run 32mpg but driven her hard it went down to 19mpg or 23mpg.
    at 135mph it does 14.7 mpg..!!!

    Can't believe got 28.7mpg out of the RS on the m4 going to reading yesterday sat at 75mph set on cruise..shocked to say the least
    #13
  14. fjtwelve
    Offline

    fjtwelve Moderator Staff Member Moderator

    Joined:
    Jan 6, 2006
    Messages:
    769
    Likes Received:
    9
    I used a Hengst air filter which is a make used by Audi cost about £9 i think has been fine. Still considering a K&N as it made an improvement on bike and previous Passat, but threads on here are not favourable.
    Sorry no ideas about gearbox threads, but haven't looked, mines 6spd manual.
    #14
  15. filipharvey
    Offline

    filipharvey Amusing Tagline

    Joined:
    Aug 4, 2006
    Messages:
    519
    Likes Received:
    0
    And how do you know this????? :whistle2:
    #15
  16. skanky
    Offline

    skanky Member

    Joined:
    Jul 23, 2006
    Messages:
    387
    Likes Received:
    0
    the DIS should show that bit of info..
    #16
  17. dreddg
    Offline

    dreddg Member

    Joined:
    Jan 7, 2005
    Messages:
    81
    Likes Received:
    0
    Around town I roughly get 28-32mpg, a mix of motorway and town about 35-37 mpg, and purely motorway about 45 mpg ( manage to do 365 miles to half a tank coming back from Lake District)

    Hope these figures help, my A6 is the 1998(150 bhp) 6 speed manual and has done 128000 miles
    #17
  18. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    Fitted new German filter Hend or somthing like that as the old one was not change in last supposd service no way did it get that black in 5k.
    i Changed it and vacumed out filter box to protect my MAF and also found the pipe letting the cool air from the front scoop was not fitting very vell so a bit of insulation tape around pipe and refitted much better and good air seal
    then went of to cornwall some 350 miles away and did 79 on motorways fully loaded up and two adults and a child and got 37.5mpg with and av speed of 64mph (i went at 2 in morning).
    drove around cornwall up and down very steep hills and not holding back and went down to 35mpg.
    Have not driven much since so time will tell.

    Now looking for remap to help with MPG and a bit of torque if poss but MPG is the main thing.

    Gears now changing up quicker after long drive too.
    #18
  19. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    Skoda dude got 47.5 mpg on the way up to scotland...
    Same engine but 163 bhp...[​IMG]
    #19
  20. rich dj
    Offline

    rich dj Member

    Joined:
    Jul 28, 2006
    Messages:
    146
    Likes Received:
    7
    forgot to say took battery off for repairing water held in car under battery problem and since reconected the car runs better?
    Strange i thought all memorys were held in non vol memory and would not loose after battery removal, i had to reset window closing ect.
    Any ideas.
    Ps still not got hold of vag-com of mate yet. Skoda dude
    #20
  21. marmite
    Offline

    marmite Counting the Tesco Club points

    Joined:
    Jul 20, 2006
    Messages:
    1,101
    Likes Received:
    0

    Did this on the way too France over a very long distance...the car got up too 145MPH but that was due to momentom and wind and going down hill!!

    OBC told me the Actual MPG and the AV MPG while I was driving:sob:

    I do miss the diesel now..did the same run to France in the RS and good it was expensive.....was showing me 4.7 MPG at 150 - 160 MPH so I kept it to a reasonalbe speed as getting to bored of standing at the petrol pump(MRS drove the rest)
    #21

Share This Page