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.
Physiology and Pharmacology. The use of anticholinergics for death rattle is predicated on the mediating role of the muscarinic receptors. These receptors regulate fluid and electrolyte secretions from enterocytes as well as the secretionof saliva.