High idle

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by rattis, May 4, 2013.

  1. rattis

    rattis Long timer

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    Hi, my best -07 990 ADV took upon it's own to rise the idle to about 3000 rpm yesterday, after shutting of the engine and restarting it it was fine.
    But today it's done quite a few times and then it woprked alright
    As I'm off to Baja tomorrow I need some advice:
    What is / was it do I need to buy some parts?
    I imagine that the amount of competent 990 mechanics in Baja are very few if any at all.
    #1
  2. DeeGee

    DeeGee I'm a Yorkshireman thanoz

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    Have you done the 15 minute idle trick??
    #2
  3. Katoom119

    Katoom119 Mmmm....Orange Kool-aid

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    I thought it was a load of voodoo horse crap first time I ever heard about it, but do the 15 min idle. Turns out the ECU does some 11010001010010 crap.

    Also, at least with mine, I've noticed that if I let the bike warm up to about two bars (I turn it on then get my gear on) that it runs better at low RPM's before it makes it to four bars. If I start it then ride it before two bars it still runs well just tries to do a little herky jerky crap. I think it takes that long for the ECU to do it's boot thing or something. But by the time it makes it to two bars either way it's good to go.
    #3
  4. Martynho

    Martynho No more Chilegringo.

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    If the 15 min idle trick doesnt work, this could be the first sign of your TPS (throttle position sensors, on the injector bodies) going south. Mine had similar symptoms then got worse and worse.

    You either need a dealer or use tuneECU to sync the throttle bodies after you install the new TPSs

    Good luck

    BTW the root cause of the TPSs buggering up was oil ingress into the airbox from a shot seal on the balancer shaft
    #4
  5. Gustavo.Ramos

    Gustavo.Ramos Long timer

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    Before you go crazy (i did), happened the same to me 990.

    what is the condition of your battery? Fluctuating current of a dying battery will mess up the ECU and idle control causing the high idle you mention.

    My case i stopped the bike, kill switch off/on and start again. Fine at 1500rev. Later riding noticed the idle was a bit high and engine braking was more a engine accelerating.

    Don't go yet mess up with the TPS. check the battery, give it a good charge, and verify the starter solenoid on low engine right. There's a small thin plate that goes to the bike contacts (2) that makes the current connection from rectifier to the battery.

    Me 990 had that little plate corroding thus the charge was random, depending on engine vibration.

    A new battery solved most of the issues, but by that time i already had mess up (tempation got the best of me) with the TPS, so added a bunch of new variables to the confusion.
    #5
  6. Katoom72

    Katoom72 Been here awhile

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    Something is steering the stepper motor, check electrical connections and health of the battery. When u turn the ignition on the stepper motor turn the intake butterfly's fully open and then closed, check if it does the full cycle.
    #6
  7. NKL

    NKL Been here awhile

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    Have you adjusted the throttle cable recently?
    #7
  8. gefr

    gefr Life is a trip

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    I had bar risers installed. They got throttle cables too tight, so when I turned the bars, the bike revs accelerated...
    Cheers.
    #8
  9. HooliKen

    HooliKen Awesome is a flavor

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    I am not intimately familiar with the intakes on the 990 but I will guess they are not a whole lot different than the ones on my 950. That said, have you checked for any intake/vacuum leaks. These will generally get worse at operating temp.

    Cheers :beer
    Ken
    #9
  10. rattis

    rattis Long timer

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    nothing worked the battery is 6 months old Li battery and there are no doubt swhen cranking , it starts like any thing and the high idle is random, but it's a bit hairy to drive in the mountains.
    So I'll have to schlepp it back to the US, which is
    the best place closest to Tijuana?
    Holiday is intercoursed!!!!!!!!!!!:wink:
    #10
  11. ÖÖ.

    ÖÖ. Ajaa kuin mummo

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    My bike sometimes gets the "high idle" -bug if I start riding immediately after starting warm engine. If engine is warm and I let it idle for 20 - 30 s after start, it idles ok.
    #11
  12. Gustavo.Ramos

    Gustavo.Ramos Long timer

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    Brilliant! :1drink

    can't proceed with holiday even with occasional high idles?
    #12
  13. rattis

    rattis Long timer

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    Going up mountains is OK, but going downhill without engine brake, you can do that.
    Lots of mountains where I'm going :D
    Safety first
    #13
  14. Gustavo.Ramos

    Gustavo.Ramos Long timer

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    been there done that, not fun ride
    #14
  15. Kobus Kruger

    Kobus Kruger n00b

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    I also have the high Idle. Very dangerous at times.

    After battery replacement no difference.
    Then I did a 15min idle and it is much better now !!!! BUT not gone. It idles now at 1800-2000 rpm whereas before it reached 3000rpm easily . Thus it seems a good reset is the answer.

    Think next for me is a TPS calibration...This needs to be done at KTM or someone who can connect to ECU. I am keeping a close eye on my idle. It is much better now and almost worth ignoring.
    #15
  16. rattis

    rattis Long timer

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    According Ramona KTM, bless them for helping me out, some, not very competent dude had messed upp the idle stepper motor, by "tuning it"!
    It cost me a new injector house combo as theyt couldn't assure me that the reset would work 100 %,
    I think safety comes first, no engine brake going over the Sierra Madre would have been hell or worse.
    !500 of Uncle S' green ones was hefty, but I can't see Manuel down the road in Creel or some other bum f.ck South American town sorting this out.
    Now it's sorted and runs well.
    Intercourse all homegrown specialists who fiddle with things they don't have the competence to fiddle with.
    Bless all the others and a second blessint o Ramona KTM , RJ and Tim :clap
    #16