MPG decrease, and coasting not at 99.9

It's colder in Seattle isn't it? You use the heater and the engine has to keep warm. That all takes energy.
Also your tyres are too soft, pump them up to at least 42/40 but I run 50/48 (front/rear).

Another thing to check is the 12 volt battery, if it's on its last legs it can suck down the mileage.

 

My garage hasn't been that warm in the morning in quite some time.

During the warmup cycle, my heater forces the engine to stay on when it would otherwise shut off. Hit the climate OFF button, and the engine quickly shuts down.

What commute distance are you driving now? What was your distance in LA? A shorter commute will explain a lot, and different traffic conditions will mess up any comparison.

 

http://priuschat.com/forums/gen-ii-...-answer-these-questions-esp-if-youre-new.html

Your temps in LA were likely MUCH higher than what we're seeing in WA. I can't vouch for the accuracy of History : Weather Underground but quick glances for LA October 2010 show temps as high as 90 F, and almost all above 70 F for highs and no lower than 50s. Compare with http://www.wunderground.com/history...tml?req_city=NA&req_state=NA&req_statename=NA: almost no days above 60 for a high, heck some not even breaking 50 and a few days (as you remember) not breaking freezing.

Looking at their stats, for LA in October the:
mean mean was 70 F, mean max was 82 F and min min was 54 F.

For Seattle in November the:
mean mean was 44 F, mean max was 58 F and min min was 15 F. .

The temp differences are huge, in my book.

Since you say heater at 72. What if you shut it off? Turn the fan and auto OFF. Having heat above LO with fan on while ICE (internal combustion engine) is cold can leave it running to provide cabin heat.

Also, "don't get the 99.9 startup when I slowly accelerate from a stop" seems to imply that you were (are?) accelerating so slowly as to not get the ICE to start. That is NOT the most efficient way to drive.

We need more info. As for alignment, well, if you think it's messed up, get it checked.

Agreed with fuzzy1's questions about your commute before vs. now, but I also ask about that in the questionnaire. Please answer them in this thread.

 

My company had me get new 45,000 mile tire at Les Schwab--36 psi max..mileage has gone from a high of 48/49 to 40/43??? COULD IT BE THESE STUPID TIRES???I HAVE LOGGED 7,000 miles.NO CHANGE??? HELP OH--SORRY--2008 GEN II CAR...NOT MY GENI CAR..

 

Yes, tires can make that much difference!

What brand/model etc tires are they?

 

I agree with Cwerdna. We need more info, specifically the distance of your average trip, and other characteristics, like prevalance of stop lights, average speed. I'm guessing your average trip is less than 4 miles, otherwise you have a battery or engine problem.

Putting your tires at 40/38 is plenty suffiicient IMO, the difference between that and 50/48 in terms of fuel efficiency isn't that much, you start hitting the law of diminishing returns. But even that wouldn't explain your low mileage, unless you have a lot of short trips. You should be getting above the 30's at that temperature in normal driving conditions.

Not getting 99.9 mpg in a coast is normal behavior if the car engine isn't warmed up yet. There may not be any arrows from the engine, but it will still be on until it's at optimum operating temperature (157'F or above while in motion). As you slow down, the effect of the running engine becomes more apparent on your instantaneous mileage number.

Tips:
1) Turn off your heater when the car is stopped at a light. This will allow the engine to turn off. (Unless the engine is really warm, then it will be able to turn off and still supply heat to the cabin).
2) Don't accelerate slowly to use only the battery power. This is an inefficient way to drive, it's been covered before in other threads.

 

Les Schwab is a great tire store, but I do not think they carry LRR tires, expect to lose 2 MPG even when inflated right. I would check the side walls of the tires for the max air pressure the tire is rated to. Subtract 2 and fill the fronts, subtract another 2 and fill the backs.

 

I grew up near Aberdeen, southwest of Seattle. One other variable that you may wish to consider is wet roads. The tire has to push that water aside and often throws up a spray of water behind the car. All that takes energy, so I never get as good mileage on wet roads as dry roads.

 

1. Yes, regarding the ICE running to provide cabin heat, at a certain point. I posted about it at http://priuschat.com/forums/gen-iii...937-poor-winter-fuel-economy.html#post1215787. Since you likely don't have a Scangauge, you can still try this experiment. With a cold engine, set the heat to hi w/fan at anywhere above off. After has run a little while and warmed up a bit, press fan OFF. You'll see the ICE stop. Then press any fan speed. ICE will start and so on... (I'm from San Jose, CA myself. It gets rather cold in the winter.)

2. Yes. Your much shorter commute is killing your mileage, esp. in the city. Just because EPA city numbers are higher doesn't mean you'll see higher city than highway numbers. You can read http://priuschat.com/forums/other-c...uth-about-epa-city-highway-mpg-estimates.html to learn more about the tests. The EPA test segments that involve a cold engine are each 31.2 minutes long and have 11 miles of simulated driving. Their tests also don't measure actual fuel consumption nor are they driven on a real road.

ConsumerReports.org - Most fuel-efficient cars shows what CR got on your gen of Prius.

3. No, don't do that. You're incurring extra losses from having to generate that power in the first place and getting it into the battery then getting it back out to run the electric motors. There's a mention of the "hybrid paradox" in the 1st PDF of http://priuschat.com/forums/gen-ii-...angauge-best-threads-mileage-improvement.html.

Since it's rather cold these days and your trips are short, you should consider grille blocking. At least it's cheap. EBH would be next but you need to be able to plug it in and it's not so cheap. (I don't have one.)

 

Hmmmm..... I can see what the issue is.. I live on the North Coast and have the same temperature range you have. The main issue is your commute distance. The EPA numbers (and other ratings) are based on longer distances with a WARM engine. It takes the Prius about 5-8 minutes on a cold day to get fully warmed up to the temps needed to get into mostly EV mode on city streets. BUT there are things you CAN do to get much better MPG averages in your circumstance. This all works for me and keeps me comfortable as well... In my city, we have a whopping 2 stop lights and a few stop signs... 2 miles from my house to the freeway off-ramp.

Here are some things you can do when you park the car overnite to help it warm up faster:
Park it in the garage. If you do this, you can put a blanket over the hood to help keep the residual heat in as long as possible.
And/or you could get and install an engine block heater if power is available. This will keep the engine warmer.

Here is the way I do my commute which gets me into the best effecient mode faster:
1) Set the heater to AUTO at 72 or 68 degrees and make sure to touch the AC button to turn off the AC pump. Leave it like this for the most part... until I show WHEN to increase/reduce it...
2) When you are leaving, tap the temperature up to 75 or 78 if you want to warm up the cabin and the HV battery faster.
3) after about 3 minutes of commute or so (3/4 mile in the city at 25 MPH), tap down the temperature on the wheel buttons to about 65-68 degrees.
4) At about 4 minutes or 1 mile or so, pull to the right, leave it in drive. The engine should shut off after about 6-7 seconds. If it does, you are now in the most effecient mode. You can turn the heat back up to your comfort range (mine is either 68 or 72, depending on my mood)...

You may have to adjust the timing a bit, but I think you get the idea... It won't make the WHOLE commute better MPG, but hopefully will get 2/3-3/4 of it back (especially with the block heater).

Just remember... The issue you are having is engine warm-up time... The computer forces the warm up cycle due to smog regulations and effeciency.

 

In addition to engine block heater: grill blocking, read up on it.

When starting cold I just accept the cold cabin for the first few minutes. When parking for the night I press the steering wheel AC button to turn it off, that way it doesn't automatically come on in the morning. After the engine has warmed up a bit, then I'll turn it on again to Auto. That's as complicated as I care to make it for myself.

- D