Prius owners, how's your mileage?

[spinbaby]

I adore my Prius, but after 100,000 miles, its mileage is definitely decreasing. My driving habits are very consistent, so I know what kind of mileage I get under what conditions. Until last I was getting an average of about 53 mpg during the summer months. This year it's more like 45. The Toyota dealer says it's working fine, but I worry about my baby.

[drm604]

1. Have you been running the air conditioner more?

This summer has been hotter in many places.

[spinbaby]

2. Nope

Even allowing for AC. Because I drive exactly the same stretch every day, I know what kind of mileage I get at different temperatures. My husband thinks maybe they're putting more ethanol into the gas mix and that's cutting down on my mileage.

[drm604]

3. Maybe.

I couldn't say. I drive an Insight, which is a completely different hybrid technology, and I've been getting the expected mileage from it since I've had it. Of course, it's only a couple years old and only has about 14,000 miles on it.

Maybe you have an engine problem, or maybe the batteries are getting old.

I have an Insight forum that I read and post on. Maybe you could find something similar for the Prius and post your issue there.

[cbayer]

4. There was some talk about Toyota adjusting mileage (somehow)

during routine maintenance checks in order to preserve the battery life.

The *rumor* was that they were shifting more of the load to the gas engine in order to do this.

I haven't done the research to see if this was ever verified or not, but you might want to look into that.

[HopeHoops]

5. That would make sense. The batteries are fucking expensive!!!

[spinbaby]

6. I'll do some googling

I do go to the dealership for routine maintenance.