[onZedge]

...First, a question. You said you idled at 1200 RPM after you snapped off the nut/stud. Did you forget to put the throttle return spring back on? I ask, because the idle really shouldn't have changed if all you did was snap off the nut/stud.

To fix it, go to Lowe's and get a 5mm x (about) 20mm long bolt or screw and a 5mm nut. Squirt a little PB Blaster on the remnant of the stud. You picture shows a little tit sticking out where it's supposed to contact the throttle lever. Grab the tit with a pliers and rock back and forth until the penetrating oil frees it. Unscrew it and discard. Now take the 5mm nut and screw it on the 5mm bolt all the way. Screw the nut/bolt assembly into the hole. With the throttle return spring attached, turn in the bolt until it just touches the throttle lever. Turn the bolt in 1/8th turn more and lock it in place with the nut you threaded on earlier. Paint on a little finger nail polish to keep it from vibrating loose (I used Revlon "Cherries In The Snow" - please don't tell my wife).

NOTE: ANYTIME YOU MESS WITH THIS SCREW, YOU HAVE TO RE-ADJUST THE THROTTLE POSITION SWITCH.

Once you reset the TPS, adjust the idle speed with the idle speed screw and not the throttle stop screw.

Hope this helps...