Newbie question

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I'll try to address just this one question!

The engine is not going to be fully warmed in just two or three minutes if you are going from a cold start. If you had the gauge installed in any other car, you'd see something very similar. A non-hybrid car is going to idle at higher RPMs as it is warming up. Later, the car's RPMs at idle will fall to the "normal" point. Much the same is happening with your new Prius. Do not be alarmed!

 

In other words, the engine is burning fuel simply to warm up. It will burn this fuel whether you are moving, braking, or standing still. Once it warms up the situation is different.

Tom

 

The engine block heater will reduce your warm-up fuel.

Ken@Japan

 

I have heard this before but am not sure how to drive in response to this. Am I best off (fuel-efficiency-wise)
1) Letting the car sit and warm up for a few minutes before driving off? Perhaps especially in winter?
2) Drive off as normal for driving the Prius (ie trying to keep below the midpoint in the HSI even thought the ICE will kick on and I won't be getting those meaty MPGs I would expect in this area after the car has warmed up)?
3) Driving a bit more aggressively than normal, up into the higher ranges on the HSI (under the theory that the ICE is going to be running to warm the car up anyway)?
4) Some combination of the above?

I have a fairly short commute (about 6 miles and about 15 minutes) and while I am getting decent MPG figures from the MID (54ish), I think this warmup period is hurting me.

(This post contains a lot of parentheticals.)

 

Perhaps on a fine, warm summer's day this would be good for you, but in most other circumstances the answer is "No." I would drive off as soon as possible. The ICE is going to do what it needs to do to warm up and make certain the HV is at an appropriate state of charge. See more below.

Yes, drive while trying to stay from placing heavy loads on the ICE. This way you won't be pressing for too much power while the ICE is looking to "set everything right." The fact is you may as well start moving the car, because the ICE is running. By sitting there your MPGs are zero.

No, I don't see the value in this. I know it has been discussed elsewhere in the Gen2 forum, and I recall the concensus was that driving in the lower power range is going to be a bit more fuel efficient at this early stage right after start -- on a cold engine, that is.

I don't really see a combo to be had, but I believe the responses change based on the weather. The warmer the weather, the less the ICE needs to work to get things "right." This gives you a chance to operate at higher efficiencies from the get-go.

 

Thanks, a priori. I thought all of my answers sort of "made sense" but you obviously can't do all of them, so good to hear what others think. I'll do a bit more searching as well.

jfveilleux, the sound is the subject of several threads. Maybe several dozen. Some find it fine, others find it horrible. A search for "sound system" or "stereo" should turn up some recent threads with people discussing what they've done. Obviously it can range depending on how much you want to spend. Some get new speakers and an amplifier, some get a new head unit too, etc.

I know I have seen people discuss the hub caps as well. Again, a search might be in order. Not sure where they are getting them from.

 

Hey I would say that's very good! I'm on my third tank and I'm usually around 4.8L/100km. The only time where I got a bit better than you was travelling to and from Whistler mountain here in BC. It's a fairly long and fast ride which I guess ends up being pretty efficient.

 

Please read five stages warm up operation.

There are huge differences between the first one minute(Stage-1A) and the rest of minutes(Stage-1B ).
During Stage-1A, the engine runs only for warm up the catalyzer and it does not provide driving power. If you start your Prius during Stage-1A, Prius is driven only by the motor, so your battery charge level is going down very quickly. That is inefficient situation.

My recommendation is one minute warm up on stand still, then start your Prius after that.

Ken@Japan

 

Thanks, Ken. The referenced writing is a classic, but I'm wondering how much of it still applies to the Gen3. Do you have a handle on that?

 

We have been observing the warm up cycle, but we have not completed yet on the Gen3.
In the mean time, it is very similar to Gen2 until Stage-3.
On the Gen3, the Stage-3 to Stage-4 transition, the idling check ceremony, is not required walking speed or complete stop.
It is done during slow down driving on the Gen3.

Ken@Japan

 

I do see a red arrow flowing from the ICE to the wheels. I assume that is a lie then?

Thanks for the warm up info. I have slowed down a bit lately on the first 300 m of each trip. I used to accelerate up to 50 km/h pretty quickly, now I keep below 40 (if I'm not holding up anyone else). That reduces battery depletion a lot, and I have more opportunity later to do some assisted glides. And after exiting the city and going to a steady 80 km/h cruising speed, it spends less time recharging the battery. During recharge, consumption is noticeably higher (~30%).

I'm gonna try slowing down more now I got this info to see if it has any noticeable effect. But I'm not going to sit and wait!

BTW how do you know stage 1B has started?