According to the EPA, the 2008 Prius is rated 48 city, 45 highway. With about half city, half interstate driving, I'm only averaging 40-44mpg. BUT, if I look here at Fuelly: 2008 Toyota Prius MPG - Actual MPG from 700 2008 Toyota Prius owners The top 3 averages are 42, 43 and 44 mpg with the averages of all fill ups at 42.3 mpg. I had Toyota check out the HV battery, which I rebuilt 2 years ago, it's not "factory new", but it's far from needing replaced (70-75% capacity of new) which is roughly what a 5 year old Prius would show. Dr. Prius app shows all the modules are fine, the temps are fine, voltage diff, etc all good. I've rebuilt the motor, put new injectors in it twice, new throttle body, new air fuel ratio sensor, new spark plugs, pretty much anything that has a bearing on MPG has been replaced. No, I didn't rebuild the motor for MPG, it was using a bit of oil and had 190k on it. Measuring things with a scan tool, long term fuel trims after driving 50 miles are only 0.78%, which is damn good. This means the car really isn't using more or less fuel than the factory parameters state as such.Short term fuel trims are good too. I've checked other obvious things like wheel resistance with the car off the ground, sticking brakes, everything. One thing I DID notice, and I'm not sure if it's because it's summer and I use the A/C, I never seem to get a "green battery" on the MFD battery charge status anymore. I'm not sure people claiming 55-70mpg are hypermiling or not, but I really can't do so because my commute has a lot of stop and go traffic, on ramps, etc so there are lots of times I have to use a heavy foot to merge. So is the 42.3 on Fuelly the "real world" average?
Yep that sounds about right as MANY factors can effect MPGs. Gosh, my V-8 Tundra got 10 mpg towing my camper this past week....it was painful filling up that gas tank!! (Makes me wonder if I really would get 20 mpg in the newer V-6 Turbo Hybrid model) For fun, I just looked up the lowest MPGs for any hybrid vehicles: 2024-Chevy Corvette E-Ray, 19 mpg 2025 Toyota Sequoia 1794 Hybrid: 20 mpg 2025 Land Rovers (PHEV): 21 mpg
The AC 100% affects fuel mileage. That compressorCruise control can go either way depending on terrain. A nice long flat highway? No reall differrence between CC and a light foot maintaining speed. Throw in some hills and it's a whole different story. A light foot will always win, since you can let the car pick up speed on downhills and then feather a bit on uphills.
I know the AC affects it, just not sure how much. Someone was telling me they put in coils out of a 1.8 in a 2019 corolla and it made a big difference. I don't think they even use the same connector or would even bolt in?
hvac effect is variable based on outside temp and humidity and cloud cover. and of course, the temp setting of the car and blower speed
So many variables for MPG. Keep in mind the Federal MPG test doesn't correspond to the way basically anybody drives. "City" can mean many things. Once our 2007 is fully warmed up (which takes a surprisingly long time, what with the silly thermos tank) it gets in the high 40's in suburban driving. That is, top speed around 40 mph and distance between stops on the order of 3-5 blocks and making the lights maybe 30-40% of the time. Take it to downtown LA (or most other major cities), with nothing but single block hops and frequent stops to avoid delivery trucks, Ubers, taxis, crazy people (many varieties), jaywalkers, and so forth, it would be more like high 30s. "Highway" also means many things. I rarely go over 73 mph even on an empty highway. It doesn't really get me there significantly sooner but the air drag goes way up. The main exception - long downhills, and even then only when there are people passing me at 5 or 10 mph above my speed, who will draw the CHP instead of me. (I'm teflon when there are yellow or red sports cars zooming by.) If all I cared about was highway MPG I would drive at 50 to 55, but that is suicide on most of the highways I frequent, other than in heavy traffic. I have seen 70 MPG on the meter while boxed into the wake of a semi while doing 73 mph on I5, but drafting like that is too dangerous to do routinely.
