I saw elsewhere in this forum that the ICE kicking in more frequently can sometimes be a sign of potential problems with the traction battery. I'm a new Prius owner (I've had my '07 with 64k miles for about 2 weeks). So, here's a poll of sorts: How often and/or at what speed does your ICE kick on when you are on relatively flat roads? After stopping for a traffic like or such, mine seems to kick on at around 17-18 mph. When cruising along at 20-35 mph with a slight downhill grade, it doesn't kick on at all. Does this seem normal?
Yes that does seem somewhat normal. You have a very light foot if you can start in electric mode and delay ICE turn on until 17 mph. But, hyper-milers will tell you that is the WRONG technique for the Prius.
You generally want to power the car with the ICE, not the battery. Ideally you accelerate normally from a light and the ICE kicks in pretty much right away. Then when you get up to speed, you back off on the accelerator and if the engine is warm and you're not using the A/C or heat, the ICE will turn off (if you're below 41 mph) and you glide like that. To power the car from the battery you're using energy converted from gas to kinetic (motion) to electricity to battery and then back from the battery again. Whole lot better to use the gas power directly, save the battery for hard acceleration and extending glides in some cases. It helps to think that the main advantage of the batteries is so that you can get by with a smaller engine for your driving needs, and so the engine can be turned off without losing lights, radio, etc.
My ICE also kicks in too often. That is a reason why I ordered a Nissan Leaf. No more ICE kicking in with a Leaf.
Yeah listen to what the others have said re trying to be overly gentle on the gas when accelerating. Typically trying to accelerate solely on electric (especially when you’re just slightly delaying the onset of the ICE) is not a very good use of the limited battery power. The interesting thing about the Prius is that a relatively small amount of electric power can save a lot of fuel if used correctly, whereas it can also be pretty much squander if used inappropriately. A typically good place to use electric mode is where you’re rolling along nicely at a slow to medium constant speed on flat or slight downhill. A little bit of electric power goes a long way under these conditions as it keeps the ICE off for a relatively long period of time. An example of a bad place to waste electric power is if you’re creeping slowly up a moderate hill, or even just "holding it" with the accelerator on a hill waiting for traffic to move, you can waste the available electric power with little gain.
I'm getting about 47-48 mpg driving my commute (which is 75% freeway and 25% city thoroghfares). On Sunday, running errands, it bumped up to 49 (no freeway, mostly 35mph city streets). I have yet to do a long trip, but that will come on Memorial Day weekend. It's an over the mountain, into a canyon, back up, and across the plains kind of trip. It will be interesting to see how it does with that.
Mileage looks good for "normal" operation. I'd say your car is in good condition re battery etc. You can learn to get better mileage. Search on this site for tips. Note that Prius will get poorer mileage at freeway speeds than secondary highway speeds. Prius does best in the type of driving you encounter around the edges of a city on side roads, but also does well -in- the city in stop and go driving.
