Sudden Bump up in MPG

satwood · 01-07-2008, 10:31 AM

Hi Gang,

I'm wondering if I just experienced the bump up in MPG that other people have reported as their new Prius' approach 6K miles. In my case I drive about 130 miles per day, all highway, with moderate to significant hills (not by west coast standards though). It's RT-290 and Rt-495 for those who know Massachusetts. My average speed is between 65 and 75 and I use cruise control most of the way. I bought my '07 Prius in November and have been getting between 44 and 47 MPG, lower end of the range as the temps got into the 20s here in December. The car now has 5400 miles on it.

Today I did nothing unusual and I got 52.4 MPG in the first 65 miles of this tank coming to work. The temperature was 45 degrees and there was no noticeable wind. I have the tires at 42/40 psi and the upper grill blocked. I use the block heater and pulse-glide on the roads to and from the highway (when I can get it to do EV only).

This increase could also be due to the warmer temp but last month we had a couple warm days and my numbers did not go up nearly that much. Is this what other people have experienced?

Before this I had managed only one tank near 50 and that was with very careful driving -- slowing speed up hills and coasting down as much as possible, keeping the heater off, no CC, drafting trucks, etc. I decided that was too much work for 49.5 MPG and then this morning it just happened. Obviously I'd like to keep this trend going.

Your thoughts?

Thanks
Steve

firepa63 · 01-07-2008, 11:07 AM

It's most likely the warmer temperature. My mileage is also up in this warmer weather.

qbee42 · 01-07-2008, 11:14 AM

Warmer temperature and the fact that you just reset the mileage calculation. The farther into a tank, the less you notice short periods of good mileage (the bumps get averaged out). I get my best mileage readings in warm weather, with a warm engine, right after I fill up and reset. Sometimes then I will average 68 mpg on the 25 mile drive home. After a few hundred miles I will be back to my normal average, which in good weather might be around 54 mpg.

Tom

satwood · 01-07-2008, 11:36 AM

Quote:

Originally Posted by qbee42

Warmer temperature and the fact that you just reset the mileage calculation. The farther into a tank, the less you notice short periods of good mileage (the bumps get averaged out). I get my best mileage readings in warm weather, with a warm engine, right after I fill up and reset. Sometimes then I will average 68 mpg on the 25 mile drive home. After a few hundred miles I will be back to my normal average, which in good weather might be around 54 mpg.

Tom

I have not been dissapointed with my 44 - 47 range so far, but achieving an average over 50 sure would feel nice. I find the reset calculation can go both ways. If I fill up at night and then drive a couple miles to home, by the time I go through a warm-up cycle the next morning it has to climb out of the 30s and creeps towards it's normal value. Other times I get similar results to yours when I buy gas mid-way through my trip. I filled the car up on Friday and did not drive it all weekend. So, the average this morning started out below 25 in the first 10 minutes and then just kept climbing to 52. The warm weather effect is really significant.

qbee42 · 01-07-2008, 12:01 PM

Absolutely! If you start up cold with low miles on the reset, the numbers are depressing. I often have a little internal conversation about the ethics of hitting reset again and purging those evil numbers. So far I have resisted, except on one occasion where I wanted to impress a skeptic.

My better averages come from the fact that I rarely drive around town. We live in a little village, and my wife and I walk everywhere we need to go. My typical trip in the Prius involves driving 30 miles to Traverse City over fairly flat two lane state highway, making a number of stops at various stores, and driving back the 30 miles. The two lane highway (M-22) is posted at 55 mph, but with tourists the actual speeds are often lower. If there is no traffic, the weather is good, and I'm not in a hurry, I'll poke along at 45 or so and get really great mileage. I've turned in runs better than 70 mpg on days like that.

Tom

satwood · 01-07-2008, 02:27 PM

Quote:

Originally Posted by qbee42

Absolutely! If you start up cold with low miles on the reset, the numbers are depressing. I often have a little internal conversation about the ethics of hitting reset again and purging those evil numbers. So far I have resisted, except on one occasion where I wanted to impress a skeptic.

That's amazing! I have the same ethics dilema

. I'm such an incurable engineer I can't even cheat on myself for entertainment purposes.

I wish they required every fuel injected car to have a consumption computer like the Prius. I find my habits have improved because of the display. Even though I don't make big changes in my behavior on the commute to work, I do skip the trips at lunch and I try to time the lights and traffic much more to minimize acceleration and braking where I can. It makes me much more aware of what I am doing and where I can economize. I think I drive my other cars differently as a result.

qbee42 · 01-07-2008, 04:28 PM

Quote:

Originally Posted by satwood

That's amazing! I have the same ethics dilema

. I'm such an incurable engineer I can't even cheat on myself for entertainment purposes.

I wish they required every fuel injected car to have a consumption computer like the Prius. I find my habits have improved because of the display. Even though I don't make big changes in my behavior on the commute to work, I do skip the trips at lunch and I try to time the lights and traffic much more to minimize acceleration and braking where I can. It makes me much more aware of what I am doing and where I can economize. I think I drive my other cars differently as a result.

Agreed. One of the secrets of the Prius is that it teaches you how to drive more efficiently. I too am an incurable engineer.

Tom

Neicy · 01-07-2008, 07:46 PM

I saw a definite jump in mpg around 5K miles, but I also had an alignment and oil change done at the same time. But I do think that part of the increase was the car breaking in. I have seen a jump just in the last two days with the warmer temps we've been getting too. It has been pitiful recently with my short trips.

Rae Vynn · 01-07-2008, 07:54 PM

Quote:

Originally Posted by qbee42

Agreed. One of the secrets of the Prius is that it teaches you how to drive more efficiently. I too am an incurable engineer.

Tom

No cure required or desired!
I wonder if the percentage of Prius owners that are some sort of engineer is higher than with other vehicles? I'm thinking that it is

Earthling · 01-08-2008, 09:21 AM

Quote:

Originally Posted by satwood

My average speed is between 65 and 75 and I use cruise control most of the way.

You drive too fast.

Stick to the speed limit, and/or look for ways to drive slower, like choosing alternate routes.

You can't expect any kind of mileage doing 75. Not gonna happen...

Harry

01-07-2008, 10:31 AM	#1
satwood Member Join Date: Nov 2007 Location: Webster, MA, New England, USA Posts: 62 My Car: 2007 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Sudden Bump up in MPG Hi Gang, I'm wondering if I just experienced the bump up in MPG that other people have reported as their new Prius' approach 6K miles. In my case I drive about 130 miles per day, all highway, with moderate to significant hills (not by west coast standards though). It's RT-290 and Rt-495 for those who know Massachusetts. My average speed is between 65 and 75 and I use cruise control most of the way. I bought my '07 Prius in November and have been getting between 44 and 47 MPG, lower end of the range as the temps got into the 20s here in December. The car now has 5400 miles on it. Today I did nothing unusual and I got 52.4 MPG in the first 65 miles of this tank coming to work. The temperature was 45 degrees and there was no noticeable wind. I have the tires at 42/40 psi and the upper grill blocked. I use the block heater and pulse-glide on the roads to and from the highway (when I can get it to do EV only). This increase could also be due to the warmer temp but last month we had a couple warm days and my numbers did not go up nearly that much. Is this what other people have experienced? Before this I had managed only one tank near 50 and that was with very careful driving -- slowing speed up hills and coasting down as much as possible, keeping the heater off, no CC, drafting trucks, etc. I decided that was too much work for 49.5 MPG and then this morning it just happened. Obviously I'd like to keep this trend going. Your thoughts? Thanks Steve

01-07-2008, 11:07 AM	#2
firepa63 Senior Citizen Join Date: Jul 2005 Location: SE Pennsylvania Posts: 436 My Car: 2009 Prius Package: #5 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Re: Sudden Bump up in MPG It's most likely the warmer temperature. My mileage is also up in this warmer weather.

01-07-2008, 11:14 AM	#3
qbee42 Senior Member Join Date: Mar 2006 Location: Northern Michigan Posts: 6,208 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 6	Re: Sudden Bump up in MPG Warmer temperature and the fact that you just reset the mileage calculation. The farther into a tank, the less you notice short periods of good mileage (the bumps get averaged out). I get my best mileage readings in warm weather, with a warm engine, right after I fill up and reset. Sometimes then I will average 68 mpg on the 25 mile drive home. After a few hundred miles I will be back to my normal average, which in good weather might be around 54 mpg. Tom

01-07-2008, 12:01 PM	#5
qbee42 Senior Member Join Date: Mar 2006 Location: Northern Michigan Posts: 6,208 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 6	Re: Sudden Bump up in MPG Absolutely! If you start up cold with low miles on the reset, the numbers are depressing. I often have a little internal conversation about the ethics of hitting reset again and purging those evil numbers. So far I have resisted, except on one occasion where I wanted to impress a skeptic. My better averages come from the fact that I rarely drive around town. We live in a little village, and my wife and I walk everywhere we need to go. My typical trip in the Prius involves driving 30 miles to Traverse City over fairly flat two lane state highway, making a number of stops at various stores, and driving back the 30 miles. The two lane highway (M-22) is posted at 55 mph, but with tourists the actual speeds are often lower. If there is no traffic, the weather is good, and I'm not in a hurry, I'll poke along at 45 or so and get really great mileage. I've turned in runs better than 70 mpg on days like that. Tom __________________ *Black* 2006 package #7 Northern Michigan

01-07-2008, 07:46 PM	#8
Neicy Senior Member Join Date: Apr 2007 Location: Wakefield, MA. Posts: 790 My Car: 2007 Prius Package: G Touring Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	Re: Sudden Bump up in MPG I saw a definite jump in mpg around 5K miles, but I also had an alignment and oil change done at the same time. But I do think that part of the increase was the car breaking in. I have seen a jump just in the last two days with the warmer temps we've been getting too. It has been pitiful recently with my short trips.