[ggcc]

Originally Posted by chuckb

Our on board computer shows 17.3 average over the two and a half years we have had the van. I always thought it would improve after it was broken in, but it really hasn't improved much. This 17.3 average includes several trips of several hundred miles each too! I know on the highway it averages 22-26 mpg,basically the 26 would be at around 55 mph, and the 22 would be at around 75 mph, and this is an LE with the 16 inch tires and FWD only. We have had several minivans, Ford Aerostars and Pontiac Montanas, two of each, that all averaged around 19-20 mpg,
but those Ford engines were 10% smaller, and all the vehicles probably weighted 10% less. And this van does about 50% suburban driving and 50% highway.

Don't forget-the size of the Sienna and the Odyssey make them no longer "minivans". These things are just about the size of a full sized van now and over 200 horsepower.

Have you try this (read the 1st post with the link) this will open more air to the intake.

Vacuum Hose Reroute Increased Fuel Economy