Toyota 2004 Prius- being less efficient


#1

Our car has about 112K miles on it, with regular oil changes and most maintenance done that was recommended by dealer-- most recently changed all belts and my husband put in a new Omega 12 V battery. In the last 5 months or so, I have seen the average MPG go from about 50 to about 38. I realize that most of this decline is due to the cold weather. As it is getting warmer, I do not see the MPG going back up. In previous winters, MPG was about 45. My husband says that it is because engines gets less efficient over time, but this to me seems a very quick decline. I have noticed that on the consuption display, the battery pack is blue most of the time and green only rarely.



Have you had this problem too?

What do you suppose is going on? I have stopped going to the dealer (because they kept trying to sell me stuff) and use our local mechanic now.


#2

Are your tires properly inflated? Have you recently changed to a different tire from the OEM ones?


#3

checked the tires last week, they are at 33PSI. The tires are in good condition, they were replaced about 18-24 months ago. They are regularly rotated and inflated.


#4

What are your driving habits? If you drive in the city your fuel mileage will be around 50. If you get on a highway for any extended period your mileage will drop to 38 or lower. It’s all about where you drive with the Prius.


#5

My husband says that it is because engines gets less efficient over time, but this to me seems a very quick decline

That’s NOT true…I’ve had several vehicles past the 300k mile mark with no decline of mpg.

As for the decline you’re seeing…

Driving habits or where you’re driving changed??
More highway driving???


#6

Does the engine seem to run more than it used to? I’m thinking that your battery pack may be starting to go bad.