text:  But when there's a vacuum leak and that throttle backs it down, that idle control, you know, it backs it down, then the vacuum leak is created. So the vacuum leak is seen and it goes up. And then the engine says, no, no, no. The computer says, you're supposed to be lower. So it tries to lower the idle. It does. It overcomes that vacuum leak. Then it drops. But then it says, oh, we're going to stall. So up it goes again. And then eventually it can.