Help - Mileage Sucks

So far low temps have not impacted my average mpg. Purchased my PIP on October. After 1 months according to the computer I was getting 121 mpg (114 mpg fuelly). At the of month 2 the computer was sitting at 137 mpg (~850 total miles).

Commute is short 3.6 miles. I park in an insulated garage on both ends of my commute (work garage maintained at 55 degrees). Weekends I errands are 10 to 12 miles RT. I can run up to 3 errands per day on the weekends.
Weekdays I only charge at work only. Weekends I charge as often as possible.
Most weekdays I can complete my commute without triggering the ICE even when the temps are in the 30 to 35 degree range. ICE warmup appears to be on a delay! 70% EV last time I checked.

 

yup, cold in ny this week. perhaps it's better to switch off EV and save it for the road.

seems unfair to single out PiP as all cars will take an mpg hit to heat up the cabin and defrost on cold mornings.

 

That's the point- even with EV mode off- when very cold outside and the engine starts for heat or for traction- it sucks up EV miles for the first few min till it's warmed up... I burn through 3 or 4 EV miles (while only getting 48-50mpg too) without even being in EV mode on frigid days... something about protecting the ICE.

 

No that's something I haven't figured out yet. When I turn the car off on my commute home (depleted battery), I average 60MPG, so not sure how it gets to 76MPG after averaging those 2 values. This is why I made this post, so you can see what kind of route I am dealing with, and how much battery it gives me, as some of the car stats can be confusing.

When I do a lot of highway driving without EV, I average around 55MPG, I never see numbers as low as 32MPG unless I did a really quick trip so the engine didn't have a chance to warm up.

 

OP, we still haven't figured out why your EV miles are so low. Again, do you get the charge complete message every morning? What is the estimated range that's shown? What is the MPG number shown on the screen at the end of that morning trip when you turn off the car? Have you started charging as soon as you get home so that you can do your errands on electric? Have you thought about turning down the heater (or completely off) and using the seat warmers instead?
Can you reset trip 2 on the EV ratio display on a weekday just before leaving the house and then snap a picture the following morning before leaving?

 

Yes, please give us more details, such as the estimated range when you unplug, especially the route speed limits, and trip/ev ratio details for each leg of the commute.

 

That's better than the 25-35mpg I get for the first few minutes in a non-PIP.

 

Has the OP answered the questionnaire yet?

Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat

I didn't even see a tire pressure reading. (Need cold pressure and ambient temperature.). Underinflated tires would kill efficiency especially on a hilly or'low temperature commute.

 

Agreed, but I'm burning up my EV charge while still burning gasoline- if you calculated the combined cost of the gas and electricity during this warm-up stage- it's probably the same as your regular Prius getting 25-35 mpg for the first few min.

It happened again this morning- and I was carefully monitoring the conditions this time...
It was below freezing here last night, but when I left the house at 11am it was already 42deg outside. I has set the cabin temp to "LO" and turned the fan to "off" last night before shutting down. This morning I pressed the start button- "EV" and "ECO" indicators were illuminated- the display indicated "charge completed" and indicated I had 9.5mi for EV driving.
I rolled out of my downhill driveway without hitting the gas pedal, when I hit the street I gently pressed the gas- not exceeding 25% on the HSI display- and the ICE started and continued to run! I hadn't even hit 15mph yet. The first traffic light I hit is .6 mi from my house (on my 30mph posted street)- the ICE is still running- I'm indicating 46mpg for that .6 mile run so far. While at the light- the ICE is still running (remember no cabin heat or fan on) now the mpg drops to 42mpg by the time the light turns green. I hit the next traffic light- the ICE is still running, it keeps running till I get about the 3 miles from my house, then it finally shuts off. At that point it's indicating 48mpg for the three mile run and the EV range is down to 7.5 miles now. So in 3 actual miles it burned through 2 EV miles and ran on gas as well most of the time for a combined 48mpg total. That's with no heat, defroster, fan,, etc... on with an outside temperature of 40+ degrees with mostly back road driving.

 

Good point.

 

You can't take two average mpg and then average them based on miles traveled. You have to break down the trips into gallons used and miles traveled, then take an average of the total figures. Here is how you would calculate it for EC numbers.

total trip = 42 miles @76mpg = 0.5526 gallons used
trip out = 21 miles @120mpg = 0.175 gallons used

Trip back = 21 miles / (0.5526-0.175) = 21 miles/ 0.3776 gallons used = 55.6 mpg

 

Sounds like some software is not written right for your driving style. I am not sure about the phv batteries when they are cold. Can you try the experiment again, but have heat on so the batteries warm up?

 

Part of the problem could be addressed by reading the last pages of the post "ICE in EV mode again". I found out that when you have a full charge and go downhill or do anything that recharges a full battery (I call it hyper-charging), that the ICE comes on. We theorize that this is to protect the Battery from overcharging. I have found that by acceleration on the downhill I actually can keep in EV. Of course of you have a to stop or break and hyper-charge the battery again it will trigger the ICE. This could be part of the problem but does not explain it all. Probably several things.

 

Actually, I think we should let the OP answer these two posts first: #86 and #89 before continuing further discussion. otherwise we're never going to get to the bottom of the issue.

 

Don't need to have the heat on... this afternoon it was a pleasant 55+ deg outside, and the car was toasty warm inside- I had a full charge and the car was in the same position in my driveway (the spot I use to charge-up) as it was in the morning. This time as I left the driveway- the ICE never came on- drove 3+ miles to the pizza place, and the 3+ miles back home- the whole time the ICE never came on. Drive my mom to church and back later on at 5pm- it was 42 outside... but the car was still warm from the afternoon sun- again the ICE never started for the 5.4mi trip. I'm convinced it's the overnight cold soak at or below freezing temps that's causing the ICE to fire up a soon as I leave the driveway in the mornings, because when I make the same run in the afternoon the ICE never fires up.

 

you could be right. it hasn't gotten cold enough here and my car is in an unheated garage.

 

1) was she in ev or hv?
2) is the ev all used up when she gets to the end of the eleven miles?
3) are you resetting a trip meter to get the trip mpg or are you not resetting and just reading it or are you reading the screen that comes up after you turn the car off?