Why did my mpg drop suddenly today?

hey there, i would not worry about that drop. I would keep an eye on the consumption gauge and drive accordingly to get the highest mpg without pissing people off.

if you're worried about your hybrid batt, drive down a hill and see if the battery is recharging. also, dont use neutral when coasting, the battery will NOT charge in neutral.

i think you're fine.

 

Yes, the Prius G2 and G3 have a variable speed, electrically driven compressor. It only runs as fast as needed to maintain the cabin temperature that is requested.

Try this sometime: start the car; let the ICE start and warmup and shutdown; the car will now be in "Ready", but the ICE will be off. Then turn on the Automatic AC and set the temperature to a very low temperature (much lower than the outside air). If you stand outside of the car, you will hear the whine of the AC compressor. It can actually get quite loud if there is a large demand on the AC. Then dial the AC back up to a warmer temperature. You wil then hear the sound decrease from the AC compressor as it throttles back.

Engine heat on the Prius is used when you want to warm the cabin, not to "warm" the AC air; this is radically different than most other production autos.

Best wishes,

 

Wow this is great news to me! Thanks!

 

You had to ask, didn't you?

http://priuschat.com/forums/gen-ii-prius-fuel-economy/63215-97-mpg-commute-aiming-100-a.html

Of course that wasn't Philly but it met the other criteria.

 

While I'm not in JimboK's league, since April my tanks have ranged from 65-70 mpg.

 

And of course there is this world record:

World record distance on a single tank for a Prius II - Japan - July 4 - Aug 16, 2006 - CleanMPG Forums

for our inspiration.

I believe the record of >110 MPG was achieved with an unmodified Prius (except an irrelevant upper grill block) and without any additional instrumentation.

 

Dominic, I'm in Chester county, so temps, terrain and commute distance are similar for us. But there are a number of other tricks and techniques that will help.

Increased tire pressure: 44f/42r.

Check that oil level is not overfull.

Install an engine block heater (EBH) I use mine year-round.

A Scangauge II will display a number of parameters that can help with better mileage.

Time the traffic lights to avoid dead stops; they are mpg killers, try to keep moving.

Analyze your routes to and from work, look for alternate paths that may provide better mileage.

For commuting, especially, you have the opportunity to analyze and refine your driving techniques since you use the same route repeatedly.

Maximum mpg can be obtained by driving 20 - 25 mph. For most of us, driving that slow is not practical, but slower is better, traffic permitting.

By the way, 55-58 mpg ain't bad at all. Like most everything though, practice is key.

Hope this helps

 

What's up with 97? Take a peek at the link for details and follow Paul's advice.

Yes, 55-58 is very respectable. I have a hunch my traffic is considerably lighter than yours. (Temperatures aren't that different.) With few cars on the road, I have considerable freedom to drive how I want.

 

Yah, well, I'm a bit hard of hearing on the right side, so I don't hear much input from the SU while driving, so that isn't an issue.
And she rarely sits at Serenity's helm.
To follow up, the last tank turned 54 mpg, so maybe I'm getting the hang of this.

 

1) The heater itself is $49 from Metro. Installation could be free; act fast and you might be able to get it in time for Wayne's EBH-installation trip next weekend. It is worth it. Whether winter or summer, it gives you a substantial jump on the warmup process. A block starting out at 140F, where you're almost at full warmup temp, is better than starting out at 80F.

2) 55-58 on the PA Tnpk is excellent! To squeeze out some more, first, keep your speed as low as traffic conditions and safety allow. From there, keep ICE RPM under control and make good use of "warp stealth" on the hills. Do a good search here and on CleanMPG for that term.

 

Good question, but since it is electric it could be variable. The fan speed is for sure!

 

Yep, mpg drop with the wife in the car.

 

I don't remember having an upper grille block during the Prius marathon 2005. But I did have an additional instrument (SuperMID) so that we could see results over 100 MPG.

How was Teddy Girl's Prius modified?

 

By The Way, the battery system draws its cooling air from the cabin (that's the vent at the far right of the rear seats), so do not hesitate to use the AC. If you are too hot then the battery system may be too hot also, in which case it will throttle itself.

 

I suggest avoiding CC in hilly terrain. CC is quite aggressive in holding speed constant, at the expense of efficient ICE RPM. Again, check out warp stealth.