Live on the smell/sniff of an oil/oily rag

Survive or get by on very little income, appears to be of Australian/New Zealand origin and dates from the 1950s. The expression was later applied to motor cars with highly economical fuel consumption that could run on the smell of an oily rag. The origin is obscure but one suggestion is that it may derive from rhyming slang, oily rag/fag, meaning a cigarette, which dates from the 1930s. The metaphor of living off the smell of a cigarette is not without merit, but is at odds with the later development of the expression into meagre fuel consumption. The suggestion that an oily kitchen rag, smelling vaguely of cooking and food, and therefore helping to sustain one, is more plausible than the rhyming slang explanation.