This One Really Pushed the Prius – A Four-Day Family Getaway!

on paper the 2010 is supposed to get better gas mileage by what many here claimed to be

"incremental", "disappointing" etc... lot of people dissed the 2010 saying it was not enough of an improvement to make it a worthwhile upgrade and i will say, i was "almost" in that camp as well (i got the 2010 for the features, not the mileage).

but this trip is made with the V package and its supposed mileage hit, so its not even supposed to do 50 mpg.

so we take a trip with a mileage hit on

weight
tires
terrain
weather
wind

what else is there? so going there with the worst of all above, you average just over EPA while driving way beyond the speed limit (EPA tests were rated at what?? 65 mph)

on the return trip, granted conditions not as bad, speed down to the limit and now we are way beyond EPA enough to bring your average for the entire trip up nearly 3 mpg...

this car has proven to have more than an "incremental" increase in performance.

 

ABSOLUTELY NOT!! if you did, you would lose sight of that 70 MPG tank!!

 

As the others pointed out, engine warm-up is important. The reason is the 1.6L Prius won't go into "hybrid mode" until the engine coolant reaches 70C. Ken@Japan brought some of the vehicle warm-up control laws that the earlier 1.6L engine, 2001-03, and 2004-09, Prius followed. In some cases, the 1.6L engine could be above 70C but still run the engine because one of the warm-up phases was skipped.

We know the 2010 Prius has an exhaust heat recovery system and so far, it looks like those earlier warm-up control laws no longer apply. Thus the engine stops at the first light or stop sign even if it hasn't fully warmed up. This is a major fuel savings in cold weather.

The cold dense air increases the aerodynamic drag because it is harder to push it aside. This increases the power demand and thus runs the engine more at any given speed. Although A/C use is reduced, it is sometimes replaced by defroster demands, the A/C running as a dehumidifier. But if the engine coolant in the earlier 1.6L Prius goes below 60C due to the heat loss from the cold, the car reverts to non-hybrid control laws and runs the engine more than necessary.

There are many subtle aspects to hybrids that take getting used to. For example, the Atkinson engine cycle is significantly different from the Otto engine by being much more efficient at low power settings. The Otto engine becomes efficient at high power settings and poor at lower power settings. But the newer 1.8L engine has features, cooled exhaust gas recirculation and aggressive variable angle valves, that maintain engine efficiency at high power settings so it runs more like a diesel in efficiency but with the light weight and regular fuel of a gas engine.

To some extent, you are seeing many former 1.6L Prius owners learning how the newer 1.8L Prius works. Many troublesome areas have been reworked and no longer drive mileage down. There are new areas, such as tire noise, but that will probably be solved when we start mounting replacement tires.

Bob Wilson

 

We just got our new Prius 2010 V with Nav last Wednesday afternoon, and promptly left Thursday for a road trip through the mountains with all our luggage (two of us). We didn't have time even to figure out how to read the various numbers on the dash, and were crushed to see what we thought were our mileage numbers increasingly going down. But when I put in a little gas after 200+ miles, we had actually gotten 48.6 mpg (figuring from the pump and miles driven). All of our little tour was up and down in mountains, and we got a bit better than that thereafter, going up to 50.4. Still, we can't figure out exactly what the consumption means, the number of the mpg on the right side, etc., and our manual doesn't seem to help much, so we continue to figure against the pump. We're hoping to get to the kinds of figures you high mileage folks are getting. But I've got to say, after driving even through mountains, we really like this car!