05' getting 40mpg if I'm lucky

The A/C compressor is one thing that can be tested in the case of poor mpg. Go out in the morning, turn the car on, wait for it to idle stop, and now turn on the A/C. It will initially make a high pitched turbine-like whine, but then step down after a bit. If it runs on high all the time, then the refrigerant charge is low or the compressor is bad, and mpg suffers as well.

 

LOL :thumb:

 

....all I can report is, 65 degree morners on the way to work I get 46-50+mpg.
On the way home in the heat I get 39-41+mpg. no matter what.
Not exceeding the speed limit improves things only slightly.
On the way to work yesterday at the speed limit I got 46.5.
Coming home doing the speed limit I watched my indicator drop steadly to 40mpg.
I live in a relatively flat region of the CA desert. One small 1000' pass on the 50 mile commute.
Seems to me the cold weather affects mileaage negatively theory remains to be proven.
There, now I'll stop. You guys are turning me into a mileage geek.

 

Rapid,

When people talk about col weather hurting fuel efficiency they are talking about sub-freezing temperatures that increase engine warm up time and maintaining engine heat at a fuel efficient level and having to use the heater to keep warm. 65degrees is not cold and doesn't have a large effect on MPG. I think your commute is either ever so slightly uphill like mine is or the AC use in the evening commute is hurting your mpg. Have you mapped the route to ensure it is flat? The first stretch of my commute appears flat but it's not and over the 5miles of road I only get 33-35mpg.

 

I think there may be more down grade on the way to work than it appears.
Also I'm going north and east in the morning.
Here 90% of the wind comes from the west, especially in the afternoon. So I'm heading into the wind for the first 22 miles of the 53 mile commute, then normally there's a crosswind the rest of the way.

 

That makes sense. See, we're turning you into a geek.

 

The crosswind will make a difference as well, though not nearly as much as the AC usage.

I had a heck of a crosswind (i think around 20mph) coming back from AC earlier this year. I don't recall the MPG I got on that trip (it's relatively flat, but a slight decrease in altitude going there), but I do recall it making my friend nauseas as the passenger. Then again, I call him a wussy (well, the "w" would be a different letter in real life) because he needs breaks between rides at amusement parks now where he didn't a few years ago.

 

lucky to get 36 mpg Re: 05' getting 40mpg if I'm lucky

I'd be happy to get 40 mpg. I've watched my mpg drop the same unexplained way on my '07. Started new at 48 to 50 mpg, 46, 42, 38 ... now I'm lucky to get 36 mpg. Yes, yes I have answered all the PriusChat questions, checked and double checked all the suggestions (thank you all but none worked), even had dealer service go over it on three separate occasions (they are useless by the way). Despite all the PriusChat advice and countless hours and money I have spent ...... my mpg continues to drop. At the rate I calculate it will be 31 mpg by the end of the year. Frankly, I can hardly wait to sell the car ... it will most definitely be my last Toyota product. Unfortunately for me: who will buy a Prius that gets only 30 mpg? Free to a Good Home: 30 mpg Prius.

 

You have a 2007 that is out of warranty already?

You're jumping to conclusions. If everything checks out ok yet you still only get 30mpg then you have a battery problem or you drive it in such a way so that your MPG suffers like driving only 2 miles per day at full throttle.

If you reset your MPG gauge and cruise on the freeway for 20 miles at 65mph on a flat surface and do not achieve at least 45mpg then something is wrong with the car IMO. Then you should take the dealer for a ride in the same conditions and if you are still getting less than 40mpg I would pester the dealer until they replace the hybrid battery while it is still under warranty.