My 1998 Honda Civic EX 4cyl 1.6L would be 0.2-0.22gph warm at idle, in neutral, e-brake on.
My 2005 Toyota Tacoma V6 4.0L will be ~0.35gph warm at idle
My 1990 Honda CRX HF...... I have no clue because it's OBD0

I'm guessing it's less than my old civic though.