Ours is a 2003 Odyssey with about 65,000 miles on the clock.
Lately is has shown some trouble climbing a long grade, which is more or less steep. In the past the minivan has had no trouble there, but as of two or three weeks ago, it feels slow climbing and is sort of shudders, like if it had a dirty spark plug.
On flat streets it also feels kind of slow. I've also noticed that the transmission shifts a little bit hard among the gears.
Because of traffic conditions it seldom shifts to 4th, let alone 5th gear.
If you read the instructions on the bottle it is for 12 gallons. Put in two bottles. t may take several treatments to work if it is an injector problem.