Greetings from another happy Prius driver

Hey welcome to the Prius community!

I wouldnt know firsthand about 0-20F weather but i'll try to answer your questions the best I can.

1/2- I would look into the engine block heater from the Priuschat Shop. Heats up the engine block before you get in so you can have heat faster and run a little more efficiently.

3- I believe the bladder is in place to help the Prius gain its low emissions rating and to keep vapors from evaporating into the air.

Others will chime in I'm sure, just wanted to give you a fairly quick response from what I understand about those topics.

Once again, enjoy your car, its a great piece of engineering

 

In any car, any electrical or mechanical energy has to come from its fuel source. 100% of Prius energy comes from gas. Thus heat, AC, radio, etc all reduce FE as they do in any vehicle. Use them as needed, but no free lunch. It takes a Prius to teach us these facts, it seems. Cold weather is a bear for FE.

Note that anything not electric would not be available when the ICE shuts down, that's why they converted more functions to electric, so they would work with ICE off. You should shut those things down when you can to save energy.

Unless you need maximum performance at startup, don't warm the car. Just let it warm up as you drive gently. 0 mpg while warming the car at a stop. If it is not working very hard, the ICE may as well be propelling you, vs doing nothing.

They felt they needed the bladder for US emissions standards, but it is gone from the 2010. 04-09's are stuck with it. Just don't overfill. Your fills will vary in amount, that is just the way it is, esp. in cold weather.

Good luck.

 

I was wondering about the reset button...I recently hit it and saw my mpg average reset to zero (obviously!). Now after I've driven it to and from work for a few days (an hour's drive, both ways) it seems I have a better average than I did before. I was at around 43 mpg average for a good month, since I reset it I'm around 46. Are you supposed to hit the reset button? I probably could find the answer in the owner's manual but.....

 

Hitting the reset button means you will start recording your MPG anew from the time you hit it. When you do is up to you. If you want to know your lifetime mileage, you never hit it. If you want to know your mileage for each tank, you hit it whenever you do a fillup. If you want to know the mileage for a trip, you hit it at the beginning of the trip.

 

I probably wouldn't use 42/40 if the roads I drove were very rough.

 

When the gas tank computer realizes that the tank has been refilled it re-sets those on-screen meters.

 

I use the database over at Green Hybrid (see the link in my signature). There is much anticipation that PriusChat will be getting its own database. There was some design work that was done last summer, but I don't know much beyond that. Perhaps one of the moderators will chime in with additional input.

I also keep an Excel spreadsheet to track lifetime numbers (I reset the MFD at every fillup so I get per tank FE that's combined to give the lifetime numbers.) Keeping this data on an exertanl also safeguards against accidentally pushing the Reset button or loss of the online resource, both of these unfortunate circumstances would result in flushing the "lifetime" total. If you don't feel that your Excel skills are up to setting up a sheet like this, I'm pretty sure that there are couple of plun-and-play versions out there

 

"Refilled" here I believe means adding more than 3 gallons of gas to the tank. I'm only about 99.44% sure of that number, but it's in that neighborhood. It doesn't necessarily mean that the tank was emptied and filled.

 

The miles per gallon only resets at fill up in early model Gen II Prius, in post 2006 you have to option to reset or not.
I have just started running 48/50 in my tyres, I know another PC member runs 60PSI.

Regen happens when you lift your foot and increases with moderate braking. Emergency braking and braking below I think 8mph uses friction brakes.

 

The braking system is a dual-circuit hydraulic braking model. When you press the brake pedal, it pushes a master cylinder as normal. That pushes the brake fluid. However, in normal operation, the brake fluid only pushes a piston in a 'stroke simulator' cylinder to give the brakes some feel and allow the pedal to move. The pressure is sensed by a couple of pressure sensors, the outputs of which are passed to the Skid Control ECU.

In a regular dual-circuit system, the Skid Control ECU runs servos which push the brake fluid to the appropriate brake pistons/actuators, and that's all - the electronic control allows better control of which wheels are braked, how hard. In the Prius, the Skid Control ECU sends messages to the Hybrid Vehicle ECU (HV ECU) telling it how much braking force it wants, and the HV ECU takes power off the main motor/generator (MG2) and tells the Skid Control ECU how much braking it's providing. The Skid Control ECU applies the friction brakes to complete the required braking force (which can be none if the motor is doing enough work).

The upshot is that the Prius uses regen braking for whatever part of the required braking it can achieve. Sharp braking causes the Skid Control ECU to apply friction brakes quickly as there's a bit of lag before regen starts. Regen capability drops the slower the motor is turning, and at about 7mph there's no contribution from regen as the creep function takes over (you'll see the arrows on the energy screen shift from green to yellow).

The dual-circuit system is also necessary for another reason: it's now common to offer vacuum-assist brakes, to increase the braking force from the driver, but the Prius engine doesn't offer a great deal of vacuum when it's running and none at all when it's not. The brake accumulator can apply more force than the driver applies with his foot.

If the Skid Control ECU detects that electronic braking has failed, it opens a couple of valves in the brake system and fluid flows directly from the master cylinder to the brake pistons.

 

Yeah, that's what I said!

 

I could have sworn that my total miles (not my MPG) reset to zero everytime I filled up. Then one day I physically hit the reset button and everything reset. I filled up my tank twice now and didn't see my mileage reset....am I crazy? I thought that used to reset...now I'm not so sure??