when I'm sitting somewhere my car just start over revving, it goes away but then sometimes it stays around for ages
Don't know much about Falcons cause we don't have them here but it sounds like it could be a sensor misread, something like a sensor telling it the electrical load is too high for engine rpm so it raises the rpm to compensate for something that really doesn't exist, I have seen this on a few Fords here in the states, power steering pressure switches have been 70% of the trouble. HTH
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