Not an erratic idle like a dirty throttle body gives you. That goes up and down when the AC compressor kicks on, and can send the idle down to 300-400 RPM and stall the engine out. Then it overshoots when the compressor cycles off.
death rattle. a sound produced by a person immediately preceding death, resulting from the passage of air through the mucus in the throat.
For other uses, see Maraca (disambiguation). The sound of maracas. Maracas ( pronunciation ), sometimes called Rumba shakers, shac-shacs, and various other names, are rattles which appear in many genres of Caribbean and Latin music.