throttle micro switch?

Discussion in 'Engines' started by **betsy**, Jul 29, 2005.

  1. **betsy** New Member

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    hi all, what is the micro switch for that is mounted on the t/body?


    looks like it is is activated at wot ?
     
  2. mk1 driver Forum Junkie

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    It's to do with the idle settings (I would imagine) and makes contact when the throttle is fully closed. From memory it is linked to the ECU, Vacuum Switch or Deceleration Valve/Cut Off Valve and the Idle Stabilisation module.
     
  3. rubjonny

    rubjonny Administrator Staff Member Admin

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    If its an 8v digifant there are 2 switches. The one on top is for WOT and tells the ECU to chuck in extra fuel when you have your foot down, the other is underneath and is the idle switch which tells the ECU to go into idle mode.
     
  4. rocco2litre

    rocco2litre Forum Junkie

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    test it with a multimeter mine wasnt working even though


    it made clicking noise
     
  5. Gareth83 Forum Junkie

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    I am converting a mk1 GTi into a 16v and was wondering about this also!

    Is it essential or should I leave it out?? It appears to go into the cabin of the MK2 [:s]
     
  6. rubjonny

    rubjonny Administrator Staff Member Admin

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    Probably goes to the ISV controller behind the centre console on the 16v :)
     
  7. Gareth83 Forum Junkie

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    I've fitted everything involved with the ISV to my mk1 16v but it is on constantly (the revs are constantly high, the idle speed was fine when engine was in the MK2)!!

    The only things I am missing are to do with the switch that is below the throttle body on the 16v!

    There are three wires going into the back of this, a black, a white and a black/yellow wire!

    I have the black/yellow connected to both pin 6 of the ECU and also the LS terminal on the control unit.

    I'm assuming I need the black and the white wire connected for the switch to work.

    Where should these connect to???????????

    I need to get this sorted so my car is then finished!!

    Cheers!!
    Edited by: Gareth83
     
  8. rubjonny

    rubjonny Administrator Staff Member Admin

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    Throttle switch wiring:
    yellow black - ignition live
    white - assume goes to the ISV control unit, or the ISV itself
    black - 'switch unit for low coolant indicator' pin 6/15 (don't ask me, Haynes description!)
     
  9. Gareth83 Forum Junkie

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    I've sorted the yellow/black wire

    There is one white wire going from the control unit to the ISV already so I doubt the white wire from the throttle microswitch goes back to the control unit?????

    Why would the throttle microswitch have anything to do with the low level coolant indicator???

    Cheers for the help johnny but that still leaves me stuck!!!

    Someone must know?? Any 16v mk1 owners there?? Singh? etc.
     
  10. rubjonny

    rubjonny Administrator Staff Member Admin

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    Yes sorry the Haynes diagram is pretty pathetic but its all I have at work, I'll update when I get home and have a read thru the Bentley ;)
     
  11. Gareth83 Forum Junkie

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  12. Gareth83 Forum Junkie

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  13. friendly1_uk New Member

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    16v switch:

    lol. i had to find another golf and copy it. not only does it want to know when your off throttle, it also wants to know when its not.

    its a simple changeover switch. the centre pin of the 3 connects to either one of the outer pins, depending on throttle possition. i think that was the order anyway...

    i cant remember one being an ignition feed, but if it is, then its going to be the common i guess.

    i know leaving them all off is bad. ive sat on the hard shoulder before fixing the bugger as i had the drawing but hadnt sorted it yet lol

    twisting all 3 together did no harm lol.
    playing about with them changes engine condition though
    Edited by: friendly1_uk
     
  14. Gareth83 Forum Junkie

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    anyone confirm that the centre wire is not an ignition live???? I thought the ignition live goes down the centre and is then either switched to show at idle or switched to show not.
    the black/yellow should be the one that goes to the ISV module and ECU?? To let it know it is in idle mode.
     
  15. rubjonny

    rubjonny Administrator Staff Member Admin

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    Well according to your ISV wiring diagram, the yellow/black wire on pin 3 goes to the ISV controller, pin 1 has a white wire which goes to the 'diaphagm pressure switch' or 'vacuum timeswitch' according to haynes.

    Edit: Pin 2 is black and goes to the fully electronic ignition controller pin 6/15, then the fusebox pin D/7 (black/yellow) which is ign live.
    Edited by: rubjonny
     
  16. Darren Smith Forum Member

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    was your car rich on tickover .ive changed throttle body it doesent seem so rich on tickover but driving now it will not respond sometimes to throttle just a dead spot an then goes again .any ideas anyone
     
  17. Rustbuster

    Rustbuster Paid Member Paid Member

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    The link above explains the system well. From memory the black yellow is live to the switch, with the switch open the black wire then sends live to the vacuum switch for cold throttle enrichment and when closed switch sends live to the ISV controller through white wire to activate idle stabilisation.
     
  18. rubjonny

    rubjonny Administrator Staff Member Admin

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    black is the ignition live to throttle switch. black/yellow is 'throttle closed' for ecu and isv. white is 'throttle open' for cold throttle enrichment system :)
     

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