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

Bad misfire under boost

Discussion in 'A3/S3 Forum (8L Chassis)' started by Welly, Dec 2, 2009.

  1. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    I'm getting a bad misfire under boost in the S3.

    It only started yesterday on the way back from crimbo shopping, went to over take something and she had a bit of a stutter. Put it down to one of those things and carried on home. Worse today, was bad on the way to work, and has now developed into a bad misfire as soon as you get anywhere close to full boost.

    VAG COM has thrown a 16514 DTC, which is Oxygen (Lambda) Sensor B1 S1: Malfunction in Circuit - intermittent.

    This code has been there for a little while now, and i thought it strange that it would start causing problems all of a sudden...

    Any ideas good people, before I am forced to burn it?
    #1
  2. s3gav
    Offline

    s3gav Member

    Joined:
    Jul 19, 2009
    Messages:
    414
    Likes Received:
    1
    mine did the same awhile back turned out to be coil pack though i never checked for a fault so may be something else on yours
    #2
  3. S3 HODGE
    Offline

    S3 HODGE Brown passenger seat.

    Joined:
    Apr 22, 2009
    Messages:
    1,202
    Likes Received:
    1
    Most likey a Coilpack as there very well known for failing after having the remap on the S3's.... or ive heard of the MAF giving these problems?

    If it is the coilpacks it maybe a better idea to bite the bullet and get all four or you may find you will be "chasing your tail". Also buy the Genuine Coilpacks there around £30 each from TPS,GSF etc....
    Hope this helps.
    #3
  4. Dani_B19
    Offline

    Dani_B19 Audi-sports own special child.

    Joined:
    Nov 9, 2008
    Messages:
    7,275
    Likes Received:
    90
    Mate you aint having no luck are you. Hope you get it sorted. Said there wasnt sumet dodgy about it though.
    #4
  5. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,796
    Likes Received:
    1,285
    Does it happen on part throttle?

    Have you logged for misfires?

    Is the misfire always there during idle, part throttle and under full load?

    If the lambda is playing up then fuelling could be all over the place... could be dumping fuel under boost and giving you the misfire...

    Try logging blocks:
    001 - will tell you how much fueling the ECU is adding/taking away
    031 - will tell you AFR
    115 - requested boost v actual

    and check 032 after a run to see what the adaption values are...

    <tuffty/>
    #5
  6. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    Think it's a coil to be fair, and if it is, it's just one of those things!
    #6
  7. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    No miss under idle, good as gold... I'm going to take it out in a bit and see whats what. Watch this space.

    Also, no misfires logged earlier in the engine fault codes.

    Got a copy of VAG COM 409 handy, are the measuring blocks the same?
    Last edited: Dec 2, 2009
    #7
  8. Dani_B19
    Offline

    Dani_B19 Audi-sports own special child.

    Joined:
    Nov 9, 2008
    Messages:
    7,275
    Likes Received:
    90
    Well i hope it is mate.
    #8
  9. Sandip
    Offline

    Sandip Well-Known Member

    Joined:
    Nov 7, 2006
    Messages:
    2,382
    Likes Received:
    60
    Sorry to sound a little basic, you might just need a new set of plugs, when mine was missing under boost last year i ended up changing loads and in the end all it wanted was plugs
    #9
  10. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,796
    Likes Received:
    1,285

    Yeah, should all be the same... coil packs usually misfire or lumpy idle...

    Private road, third gear from 2k rpm to redline... usual story

    <tuffty/>
    #10
  11. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    All sorted :)

    Took each pack out in turn and gave it a bit of love. A bit of corrosion on the electrical connector on cyl 3 I believe was the cause (must of been - wet fuel still on the spark plug), still, all good now. WD40 and a bit of 800 grade wet and dry. Did all of them for good measure. Problem gone.

    *Big Sigh*
    #11
  12. S3 HODGE
    Offline

    S3 HODGE Brown passenger seat.

    Joined:
    Apr 22, 2009
    Messages:
    1,202
    Likes Received:
    1
    Ahh good man. Car must of been sat around for a bit before you bought it?
    #12
  13. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    Yes, I believe it has been for a substantial period of time. Poor old girl :(
    #13
  14. S3 HODGE
    Offline

    S3 HODGE Brown passenger seat.

    Joined:
    Apr 22, 2009
    Messages:
    1,202
    Likes Received:
    1
    Just give her a good service and a nice fresh tank of fuel and she will treat you well :)
    Godd buy tho mate, I heard how much you payed for it!
    #14
  15. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    Cheers dude, thats exactly what I plan to do. I only run my cars on V Power or Tesco 99 because it makes such a difference I think. Plus much cleaner burn.

    Just ordered all servicing kit for her as well - so that will be a job for just before Xmas!!
    #15
  16. S3 HODGE
    Offline

    S3 HODGE Brown passenger seat.

    Joined:
    Apr 22, 2009
    Messages:
    1,202
    Likes Received:
    1
    Good stuff, Yea ive always run mine on V-power! Seems to burn quicker but well worth the few extra pence ;)
    #16
  17. Welly
    Offline

    Welly VX220 SC Driver :)

    Joined:
    Aug 5, 2009
    Messages:
    10,699
    Likes Received:
    117
    To be fair, when I tickle it around, I get better MPG on V Power. Problem being I never tickle it anywhere :(
    #17

Share This Page