Maintenance increases MPG

andyprius · 01-31-2009, 07:16 PM

On 01-26Ken Kneeb, post #31 posted an observation on " Dead battery after 2.5 weeks. He noted a 20% increase in MPG after replacing 12V with a new battery, and also in continuing to charge

battery daily. I have essentially done the same thing, but not with a new battery, but one that still had some life in it. Open voltage reads about 12.67 VDC. I just finished a Casino trip to Reno and noted 45mpg upon arrival. On return I tanked up and pulled into my garage with 53.9mpg. This was winter driving, with temps of 18F at the peak of the Sierra Nevada range on Route 80. I would like to hear of anyone else noting this observation. It does make sense that the HV circuitry could use its energy in a more productive way, instead of constantly trying to charge a weak, semi-depleted boot-up battery operating in the 9-12 Volt range.

dogfriend · 01-31-2009, 11:16 PM

I recall others reporting poor mileage as a result of a weak 12V battery.

01-31-2009, 07:16 PM	#1
andyprius Senior Member Join Date: Feb 2005 Location: Sacramento, California. Posts: 779 My Car: 2005 Prius Model: Package: #3 Thanks: 3 Thanked 1 Time in 1 Post Friends: 1	Maintenance increases MPG On 01-26Ken Kneeb, post #31 posted an observation on " Dead battery after 2.5 weeks. He noted a 20% increase in MPG after replacing 12V with a new battery, and also in continuing to charge battery daily. I have essentially done the same thing, but not with a new battery, but one that still had some life in it. Open voltage reads about 12.67 VDC. I just finished a Casino trip to Reno and noted 45mpg upon arrival. On return I tanked up and pulled into my garage with 53.9mpg. This was winter driving, with temps of 18F at the peak of the Sierra Nevada range on Route 80. I would like to hear of anyone else noting this observation. It does make sense that the HV circuitry could use its energy in a more productive way, instead of constantly trying to charge a weak, semi-depleted boot-up battery operating in the 9-12 Volt range.

01-31-2009, 11:16 PM	#2
dogfriend Human - Animal Hybrid Join Date: Feb 2007 Location: Carmichael, CA Posts: 4,971 My Car: 2007 Prius Model: Package: #6 Thanks: 289 Thanked 175 Times in 147 Posts Friends: 11	Re: Maintenance increases MPG I recall others reporting poor mileage as a result of a weak 12V battery.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
transmission hum gets louder as speed increases	vince31	Gen II Prius Technical Discussion	26	05-10-2009 02:13 PM
What Other Used Car Increases in Value?	Linda L	Gen II Prius Main Forum	0	07-11-2008 10:52 PM
Emissions from autos sold in U.S. increases	cwerdna	Environmental Discussion	1	09-03-2007 10:59 PM
Thudding sound that increases with speed	agill	Gen II Prius Care, Maintenance and Troubleshooting	15	07-28-2006 04:16 PM
Used Prius Increases in Value	Spunky	Gen II Prius Main Forum	0	03-13-2006 09:03 AM