I'm planning on buying a new car in 2008. Here's the scoop: When I bought my HCH in autumn 2002, I chose that model over the Prius because 90% of my driving was highway miles at 65-75 MPH. Honda's IMA can assist the engine at any speed, and I didn't need an EV mode (because I just didn't do much in-city driving).

Well, that's all changed now. I got a law enforcement job downtown, and my driving is now 90% city and 10% highway. This seems more favorable to a Prius HSD than a Honda IMA.

Here's what I'm wondering:
-- How much of a 4.1 mile drive can an unmodified Prius do in EV mode?
-- How far inbetween stops do you have to drive before autostop can function?
-- Has anyone had any *real* problems with this car (i.e. problems that involve safety and drivability?)

Don't get me wrong: I *love* my Civic Hybrid. But it's just not optimized for how I have to drive now.

 

Hi Ashen,

It is hard to predict what will be in the 2008 models. I drive an 03 Prius, NHW11, but my understanding is the current Prius, NHW20, does not come with the EV button in the States. There is a vendor who sells a kit to put on in.

Although the EV is attractive, one engineering problem is that energy still needs to come from somewhere . . . pay me now or pay me later. The "Plug-in Prius" folks have addressed it by adding batteries and plugging into the grid.

I've missed any analysis of 'autostop' mode but the Prii community has been mapping the operational modes associated with warm-up. In my NHW11, autostop seems fairly quick, seconds, after the car stops.

Other than the proverbial limited rear view shared by almost all Toyotas, none that I know of. The fleet data suggests some weakness in the steering gear but more of a handling and maintenance issue than safety. I've also seen some postings about body 'stiffening' for the NHW20 models but the impression is it is for handling performance.

Good luck!

Bob Wilson

 

you should also try out the new hch ii and compare against comparable prius ii. the reason why i say this is that the hch ii and prius have completely different approaches to hybrid technology. both yield about the same average mpg (highway/city) combined. it's been said that hch ii is better at highway mpg than prius ii because of the advances in the ice. however, i'm not certain if there is any real data to support this. the data here and at fueleconomy.gov both record combined city/highway mpg. so there is no breakdown. technically speaking, the prius ii has more battery storage and a bigger electric motor than the hch ii. that would imply that it may be more efficient at lower speed city driving where the electric motor can supply more of the power needed to propel the vehicle. *however*, you have to keep in mind that the ice in the hch ii is more efficient than the prius ii. just because more of the power comes from the ice vs. the electric motor doesn't mean that the mpg is necessarily less. it could be that the net amount of fuel consumed by both vehicles in city driving is basically the same. this is why i'm saying you should test drive both in a real environment before making any decision. my gut tells me that both cars would roughly yield the same city mpg if a database existed that could collect only that data.

in the end, i don't think you can make a mistake by choosing either a prius ii or an hch ii. good luck and let us know what you find in a real world comparision!

cheers,
neil

 

For those who are are so inclined, the EV button can be installed for about $3. EV mode can be invoked via the button at powerup, preventing the engine from starting, as long as the ambient temps are between approx 40 and 90F.

Otherwise, EV mode can be invoked via the EV button after a few minutes of engine running. EV mode will not occur by itself until the coolant temperature reaches 70C.

Most of the time, the Prius traction battery will be at the targeted 67% SOC. In that case, you can travel about 1.5 miles over fairly flat terran at 25-30 MPH speeds. If the battery is fully charged, you can travel for about 2 miles.

Once the SOC reaches 40%, EV mode will be cancelled. You will hear three beeps and the engine will start.

I have never driven an HCH. But from what I understand about IMA and HSD, for city driving, the advantage goes to HSD IMHO. I have had great success with my Prius in city driving, easily beating the 60 MPG EPA estimate.

As for highway driving both the HCH and Prius are equivalent unless you have the patience and technique to take advantage of the Honda Lean Burn. In that case, the advantage goes to the HCH.

I have 63k miles on the Prius and have had absolutly no problems. It has never been to a dealership for service of any type. I perform all of the service myself.

Hope that helps.

 

Hi Niel,

You may want to look at the individual vehicle data within a vehicle class. A month or so ago, someone was curious about the highway versus city mileage for Prius. It turns out you can find individual vehicle data with relatively high or low ratios of highway vs. city mileage. Just 'cut and paste' their data into an excel spreadsheet and plot out the MPG. No doubt simular data exists in the Honda sets.

BTW, the Prius Atkinson cycle achieves pretty good efficiency by holding the intake valves open during part of the compression stroke. The intake compression ratio is 8:1 while the expansion ratio is 13:1. This reduces the energy needed to compress the charge and reduces starting energy demands. It is also why the 1500 cc engine in our Echo is rated at 108 HP versus 70 HP in our Prius I.

Bob Wilson

 

I am truly impressed. My city average is 43-47 ('04 Prius, 38K miles) in the summer and 39-42 in the winter. Most of my city driving consists of a 5 mile commute. The engine does not have time to warm up to an efficient temperature before I arrive either at home or at work.

I generally get about the same on the highway, a little better if on secondary roads that I can drive at 55-60 mph.

Is there a secret to your much better mileage other than driving for longer distances?

Thank you.

Bill Allison
wtallison@gmail.com

 

I wish I could give you a silver bullet, but a 5 mile commute will yield a low FE no matter what vehicle you drive. Your numbers are pretty good considering. YOu would be a good candidate for an EV.

 

Who know what will be available in 2008? That's a totally speculative question. Most Prius owners *hope* Toyota will provide a plugin option for a large lithium ion battery pack. But that is just a dream right now. So all I can comment on is current technology.
--> How much of a 4.1 mile drive can an unmodified Prius do in EV mode?
At what temp, is the car warmed up, what terrain? All of these factors affect EV mode driving. If the car is warmed up and on reasonably level terrain and one doesn't have a lead foot, with current technology one might be able to do a mile or two in EV mode, assuming the battery has a good charge. With a LIon pak that was charged overnight, one should be able to do the whole trip with a light foot.
--> How far inbetween stops do you have to drive before autostop can function?
As soon as the car's catalytic system is warmed up. More in the winter, less in the summer. Right now, this takes 5-10 min. at 35 degrees.
--> Has anyone had any *real* problems with this car (i.e. problems that involve safety and drivability?)
Reliability has been very good so far. Some Priuses are in service as taxi cabs. There was an issue with some 2004 models stopping, that was fixed by a software upgrade, but overall its service record is very good. The European auto safety institute just gave the Prius a 5 star safety rating.

 

Actually, I have an EV, but can't tell that it makes any difference. Although it seems that it should, the truth is, that the battery gets drained pretty quickly, and then needs to be charged. The time it takes to charge it back up is just about equal to the remainder of the commute. So, what I have saved by using the EV gets paid back when recharging the battery.

After my post, I went back and checked my records and it appears that I have actually done better than I thought. My overall average is very near the average posted here, 47 mpg.

I have just recently begun inflating my tires to the average of the manufacturer's recommended tire pressure (32) and the max sidewall pressure (44) or 38 psi. I am interested in seeing how that impacts my mileage. I am leaving for a trip Monday that will take me from the flat lands of Louisiana to the mountains of North Carolina, an 800 mile trip that I have made many times. It will be interesting to compare my fuel economy to previous trips.

 

My biggest complaint about the Prius 2 is the blind spots. The driver's rear side blind-spot is bad. There's an awful blind spot, on the passenger-side, where the frame connects the right front hood to the roof. If you're making a left-hand turn, from a secondary road, you'll notice it. The view out the back is obscured by the spoiler. WTF were they thinking, with the rear-view?

After eight months, I still have problems with the blind spots. In other cars I've owned, I check the spots once. In the Prius, I have to check them twice, every time.

All that said, I love the car and have no regrets. Double-checking your blind spots is a good thing. I just wish the car didn't force me to do it.