We purchased a PIP back at the end of April of last year for my wife's work commute of 60 miles. We started using Fuelly to track all of the fuel ups and have not missed any. The car is charged nightly at our home and more often on weekends. There is no where to charge at her work. We live in San Diego so the temperature is pretty moderate. She takes the same route daily and her other driving routines are pretty consistent. Our first month Fuelly report averaged 58.5 MPG and 59 in August. It has since been dropping and is down to 52 MPG for the last two months. Is anyone else having this issue? Even in a mild climate could this be temperature related? We are feeling 52 MPG is not great for a PIP and we are at the low end of the curve for the Fuelly tracked cars. Thanks in advance for any advice.
Yes! some of it could be temp. related, if the temp has fallen to between 45-60 degrees. There ar also many other reasons check this FAQ page for other possibilities. Why mileage gets worse in winter | PriusChat
Along with a drop in temperature, you may have also lost air pressure in your tires. If you havent already done so, air them up to around 40-42psi or so (I try to keep mine at 42 front/40 rear).
Also remember using any heat on a higher setting 72 and above or fan speed higher than # 2 Will hurt Mileage quite bit!
The best comparison is the same months a year later. Another factor is winter vs summer blend of gas. Mike
A 10% drop in fuel economy over winter months is not unheard of. I'm more concerned at your overall fuel economy. 59 mpg would be pretty lousy for a PiP in the winter and you get that in summer. We can better determine if there is a problem with more details about your commute and your fuelly stats.
Your EV mode is most efficient at low speeds so if possible use 25-35 mph. If all freeway it really eats up battery but it does also give you a increase in mpg. So if all freeway driving go ahead and use EV Just like bisco said but still drive safe!
Thanks for all the responses. It sounds like a combination of a number of things going on. Her commute is at least 40 freeway miles and I am sure she is doing 65 to 70 in the car pool lanes. I will find out her heater settings but I know she likes the seat warmer. I didn't know that the gas blend change could have such an impact. I am more of the green person of the two of us. I don't think she is driving to stretch miles like I do. My guess is the temperature and heater may be the biggest issue. I will go check the tires now. Thanks. Pat
