I know plugs and coil intervals are a sticky topic, some say you need them every 100k and some say 200k or until they fail. Anyway, I just got a 2017 Prius Three two days ago, car has 120k miles. The carfax shows the car was maintained at Toyota dealership before, but mostly brakes and suspension checks, unsure if it received ignition service previously. Anyway, the car does 52 mpg right now after I reset the fuel economy. I live in northeast Arkansas and it's not hilly, tires are good and I drive decently, not too fast or slow... Hardly traffic jams in my town, mostly cruising at the speed limit. When I bought it, the screen showed 37mpg since the dealer only moved it or drove on short trips, so after the reset my avg. fuel economy is 50-51 after 500 miles of driving from Nashville, TN. So I guess the display is correct for my real life MPG. But since many people say their Gen 4 get 60-70, I wonder if this means my plugs and coils are due?
FIRST....I will answer the question. They're lying.....and...No. TANK averages for your car of 50-ish mpg, hand measured - are above average. YOUR Warranty and maintenance guide: https://assets.sia.toyota.com/publications/en/omms-s/T-MMS-10Prius/pdf/2010_Prius_WMG_0W20_lr.pdf Be careful replacing the plugs with fakes or paying somebody that might....(Amazon.)
Driving technique has to be improved to get higher than rated mpg and even then it requires minimal ac and maximum thought about easy acceleration and early slowdowns.
This is the internet; people are people and some delude themselves thinking things are true that are NOT. Attached is the Mornoney sticker for a similar Prius. This is what you should expect - No inflated BS...... People can get more mpgs, but that's dependent on how they drive and under what conditions. I'm averaging 135 mpg, per my odometer; but mine's a PHEV and I'm mostly around 30 miles round-trip. I don't go around telling everyone all these cars will average 135 mpg......... Window Sticker for 2017 Toyota Prius Three Touring In additional to what's due, per OEM maintenance - coolant change, brake system flush, and ATF change; if they've never been done. I usually change ALL fluids every 100K on all my cars; it's cheap insurance. In my experience, ignition coils will usually go 200K+, before they begin to intermittently misfire. I've had cheap knock-offs fail in as little as 25K. Hope this helps......
Here's a table-format translation of the aforementioned (Toyota USA publication) Warranty and Maintenance Booklet, a little easier to read, comprehend. Both excel an pdf versions, per the booklet, and extrapolated to 240k miles (or 24 years).
