idle going up and down

[bustedplastic]

so when i start my quad, the idle will go up and down and up and down and it confuses me.  What is causing this?  My buddy messed with the scre circled in the picture, but i dont know what that does, does anyone know what that is and should i hit him for messing with it?  I dont know how many turns he did so i dont really know if this screwed it up...

[Warren]

i don't know what screw that is he messed with but i know it's not the idle screw. lol. i can't tell really which screw that is without the rest of the pic. but i know it's not the idle screw. so yeah you should hit him. 

[tonyrt44]

this is the air bleed screw, something like that !

what other mods ?

when my ignition module went bad, I had the same issue like yours.

could be electrical !

[Livingmylife93]

Mine started doing this today too... I was kinda hoping it was doing it because it was over heated or something...

[air]

The TPS will cause erratic Idle also

[09RappySE]

That is the cold idle adjustment screw, it should be 5 1/8 turns open.