I have this question which really puzzles me.
I'm from Europe and used to drive manual. I used to shift to neutral going down the hill to save on gas. Now I moved to the USA and I have cars that use automatic transmission but I was still thinking that I can use Neutral when going down the hill.
I have Honda Odyssey(05) and Ford Taurus(10).
When driving down the hill Honda I tend to use neutral. The idles go down as it should. No problem here.
When driving Ford in neutral the idle speed tends to go into higher cycles based on how fast the car is moving down the hill. This confuses me as it makes the meaning of using natural pointless. This was also happening with my old Ford. I thought it was a defect and thought when I buy a new Ford it will be OK. Any idea why Ford accelerates idle speed in neutral based on how fast the car is moving?