990 Adventure TPS problem?

Discussion in 'Dakar champion (950/990)' started by DC1200, Jan 19, 2011.

  1. josea1952

    josea1952 Been here awhile

    Joined:
    Apr 13, 2011
    Oddometer:
    394
    Location:
    Avon Lake, Oh
    Ok, 990 adv abs, 2007, 72k

    I've been neglecting an issue with I erratic idle for a while mainly because the bike was "rideable". Now it's just unbearable, I have random idle spikes to about 5k and it's very unpredictable.

    Black and yellow read about .69 to .72 with it closed, open throttle read 3.764.

    Everything else seems to operate as advertised. Is that slight adjustment really the fix or is it just a sensor going bad and dropping out of range? Should I just bite the bullet and buy the tps and not mess with it? That hundred bucks sure seems better than an entire day of troubleshooting and adjusting.
    #21
  2. speedy 1

    speedy 1 Wizard

    Joined:
    Jan 26, 2013
    Oddometer:
    566
    Location:
    Dark Coast Southern Oregon
    the last one I replaced tested fine across the range
    ohm readings off the bike and voltage readings on the bike were within spec
    a new one made a remarkable change in performance
    when in doubt ... change it
    #22
  3. rossguzzi

    rossguzzi 990 Adv.

    Joined:
    Oct 21, 2012
    Oddometer:
    2,657
    Location:
    Bottom left hand side of OZ
    What`s involved in changing one as far as setting it up to speck again? Use TuneEcu or a multimeter ?
    Wondering if it should be a spare carried on long trips and if it can be set up without laptop around.

    Does it improve the feel of on off throttle snatch at all ?

    Cheers
    #23
  4. Gustavo.Ramos

    Gustavo.Ramos Long timer

    Joined:
    May 19, 2008
    Oddometer:
    1,241
    Location:
    Accross the pond
    If running the stock airbox you need to take out the TB's out of the airbox, that includes taking the tanks, crash bars (if you have them). disconnect the tps connections, release the holding screw and replace the tps sensor. Keep in mind there are two of them, you don't want to replace the wrong one! Its the front one when seating on the bike. A multimeter is good to set the tps, but tuneecu will be better.
    #24
  5. rossguzzi

    rossguzzi 990 Adv.

    Joined:
    Oct 21, 2012
    Oddometer:
    2,657
    Location:
    Bottom left hand side of OZ
    Cheers, dosnt sound too hard. Might get one as a spare, just in case.
    #25
  6. gefr

    gefr Life is a trip

    Joined:
    Nov 26, 2005
    Oddometer:
    5,042
    Location:
    East Med, Greece
    TPS will easily last 40k kms. I see carrying one as overkill.
    Cheers
    #26
  7. rossguzzi

    rossguzzi 990 Adv.

    Joined:
    Oct 21, 2012
    Oddometer:
    2,657
    Location:
    Bottom left hand side of OZ
    It could be overkill, but ........

    When setting up a new one, should the idle screw be backed off so the butterflies return all the way. or leave the idle screw as is and just let the throttle return to the off position ?

    Cheers.
    #27
  8. Gustavo.Ramos

    Gustavo.Ramos Long timer

    Joined:
    May 19, 2008
    Oddometer:
    1,241
    Location:
    Accross the pond
    Just apply the least variables as possible. the stepper motor should do the trick.
    #28
  9. Deviant666

    Deviant666 Been here awhile

    Joined:
    Jan 23, 2010
    Oddometer:
    701
    Location:
    Athens, Greece
    I'm experiencing a similar situation. I've been informed by a KTM mechanic that sometimes the TPS will show correct voltage when measured but it's worn out anyway. I'm going to bite the bullet and buy a new one. Idle stepper motor is deactivated from TuneEcu so it's not involved in this whatsoever...
    #29
  10. Gustavo.Ramos

    Gustavo.Ramos Long timer

    Joined:
    May 19, 2008
    Oddometer:
    1,241
    Location:
    Accross the pond
    try disconnecting the battery, flip the key on to draw any residual current. Reconnect the battery, start the bike and let it idle still for 15 minutes.

    I've been skeptical about this in the past yet I've seen it work (or attenuate) such high idle behavior.
    #30
    Benduro likes this.
  11. josea1952

    josea1952 Been here awhile

    Joined:
    Apr 13, 2011
    Oddometer:
    394
    Location:
    Avon Lake, Oh
    Well, I ended picking up a used set of TB's off of an inmate. Changed them out, went to do the oil and found a wavy filter, so water pump rebuild it is, eventually I'll see if the TB's fixed it.

    Like I stated in a bother thread, having avionics background on military aircraft, it drives me nuts there's no way to determine without a reasonable doubt when a sensor or stepper is bad. Not to mention when you call dealers and you find out they can't fix the shit either, they just throw parts at them.
    #31
  12. gefr

    gefr Life is a trip

    Joined:
    Nov 26, 2005
    Oddometer:
    5,042
    Location:
    East Med, Greece
    Yep, that's exactly the case. Reliability is not so high priority in bikes. Cheap systems with limited longevity are used. Water pump, fuel pump with points and technology way old and unreliable, R/R with old technology.
    Cheers.
    #32
    Benduro likes this.
  13. Defaultgateway

    Defaultgateway Adventurer

    Joined:
    Nov 29, 2011
    Oddometer:
    93
    Location:
    Shortpump, Va.
    Here is a measurement of a new 990 ADV LC8 (ktm p/n 61041077000), there are two but they are electrically the same.
    blu wire +4.984 from supply
    blk wire is ground ref.
    Yellow is signal out (wiper of pot)
    nominal sensor is 0 to 5,000. ohms
    Note, the main point is not the slope or if it is a straight line, but that the voltage out signal goes from 0 to the supply rail without any dropouts or spikes, and moves from 0 to rail voltage (your supply voltage) with full range and repeatable.
    Cheers... defaultgateway
    #33
  14. rider911

    rider911 Shortcut Navigator

    Joined:
    Sep 18, 2009
    Oddometer:
    1,280
    Location:
    Australia
    With regard to fault finding, you cant measure that voltage with a digital multimeter, the sample rate is far too slow to pick up anything except major failures
    #34
  15. josea1952

    josea1952 Been here awhile

    Joined:
    Apr 13, 2011
    Oddometer:
    394
    Location:
    Avon Lake, Oh

    What would you use to see that, that is not absurdly priced for the common household?
    #35
  16. rider911

    rider911 Shortcut Navigator

    Joined:
    Sep 18, 2009
    Oddometer:
    1,280
    Location:
    Australia
    You need a oscilloscope. The cheapest way to go is a computer based one where you use your laptop screen to display the readings. You will need a little bit of nous to set it up though.

    There are handheld scope meters but theyre not cheap here although you guys in the states probably have a bigger used market than we do. Search for one of these on ebay
    http://www.motor.com/magazine/pdfs/052001_11.pdf
    The Snapon Vantage is very easy to use.

    These are useful and have plenty of accessories.
    http://www.ebay.com/sch/i.html?_fro....A0.H3.Xhante.TRS0&_nkw=hantek+1008c&_sacat=0
    #36
  17. Adventurer2

    Adventurer2 Adventurer

    Joined:
    Apr 3, 2006
    Oddometer:
    19
    Location:
    South Africa JHB
    I have had similar problems for some time now, 2007 990, I checked the TPS voltage today, between the white and black wire off the TPS plug, 0.67V closed, goes up to 1.9V at around half throttle, then voltage falls away to zero V....I am using a digital multimeter, I don't have one of those fancy gadgets available in the USA, could the TPS be faulty? Bike runs perfectly fine right up to full throttle, but idles erratically after a short ride, throttle reset and it's good for a short while, then revs high again....
    #37
  18. rossguzzi

    rossguzzi 990 Adv.

    Joined:
    Oct 21, 2012
    Oddometer:
    2,657
    Location:
    Bottom left hand side of OZ
    If you can, I would check with the TuneEcu linked up. It could be a fauty Mmeter.
    #38
  19. Gustavo.Ramos

    Gustavo.Ramos Long timer

    Joined:
    May 19, 2008
    Oddometer:
    1,241
    Location:
    Accross the pond
    if the high idle is only occasional and managebale, i'd leave it alone if you do not have the proper tools (tuneecu), etc.. the TPS is a sensible bit and i've had my share of headaches with it.

    so far from friends around with similar symptoms, i've disconnected the battery, flipped the key on, then off, just to draw residual electricity from the wiring and then reconnected the battery. After that start the engine and let it idle for 15 minutes. Often the bike just goes back to its normal state, as if it was just requiring some TLC.

    If this does not work at all, the idle goes to +4k rpm and you feel the engine is totally out of control, mostly noticed when engine braking that the high idle does not allow to brake and you feel the bike almost like accelerating, then you should try something different like adjusting the TPS voltage or in worst case replace the TPS.
    #39
    Benduro likes this.
  20. Adventurer2

    Adventurer2 Adventurer

    Joined:
    Apr 3, 2006
    Oddometer:
    19
    Location:
    South Africa JHB
    Multimeter is 100%, checked with another one, same results. I've had the ECU reset at a dealer, done the 15 min idle reset, but have not disconnected the battery before doing this, will try this. This problem persists, in a 20km ride I have to reset about 4 times, real PIA, but I will do this battery disconnect thing and then the 15 min idle reset....here's hoping it sorts it...
    This drop-off after 1.9V is very strange, the bike runs perfectly right through the rev range, it just idles high....Thanks for the feedback so far, always open to new suggestions.
    #40