Get ur self a return spring that goes around ur carb. that really hells to pull the carb closed and keep it from pulling back open, more then the 1mm u need...And yep sound like ur clutch spring is shoot..A worn or broke n spring can make ur car /truck act funny in a few way...
1. if broke , it will make the car start move n at idle.
2. cause it to stall.
3. makes it hard to get it started
4. make low end power. very sloggish.
so check or replace that spring.