The body of a deceased woman was found in a car. The circumstances were typical for suicidal carbon monoxide (CO) poisoning by inhalation of exhaust gases, except that the vacuum cleaner hose had become detached from the exhaust. Autopsy revealed only decompositional changes. No CO or other drugs were detected. Hypoxic changes were present in the cortex and hippocampus, with an age of 2–3 days. It is consistent that this woman inhaled sufficient CO to cause coma, at which stage the hose became detached, and that she then exhaled CO over the next 2–3 days before finally dying. Delayed death following CO poisoning is an uncommon occurrence. This case is reported because of its unusual nature.