Had a long motorway drive the other day, air con off, cruise control on for most of journey. Decent weather, UK gallon (4.55 Litres), reset MPG monitor some way into journey while doing about 65 mph. 53 Miles later, without stopping, my average was 75.5 MPG. I did drop my speed to around 55 mph just to see how high I could get my MPG. Arrived at destination parked for about 3 hours, then returned home covering 273 miles (some slow traffic and didn’t go over 80 mph) from reset, averaged 70.7 MPG. I didn’t think this was possible, seems a lot better than official figures would even suggest. I thought maybe the meter was faulty but it seemed to be about right what with fuel used and distance travelled. I’m not complaining but wondered if something could be wrong, e.g weak fuel mixture or something. Any thoughts? See photo’s below.
70.7 miles/Imperial gallon = 58.9 miles/US gallon That is quite good, and if the check engine light is not on then you don't have to worry about the air/fuel mixture.
There is continuous monitoring and adjusting of the mixture, so your good MPG is due to being in the sweet spot of temperature, terrain, and speed. Add some large hills, cold or heat, and the frantic pace of US interstates, and MPG's will reduce. (I don't know about your M-ways and speed limits, and how they are ignored.)
Don't overlook the fact that he is resetting while the car is moving on the freeway after the ICE is warmed up. I bet if he reset with a cold ICE and then drove those routes, he would NOT get those kind of numbers. Just my opinion for what it is worth. The following is copied and pasted from the OP first post - reset MPG monitor some way into journey while doing about 65 mph Read more: http://priuschat.com/threads/75-mpg.138946/#ixzz2wkviJx4G Follow us: @PriusChat on Twitter | PriusChat on Facebook
The 75MPG is probably a little higher than actual because of cutting out the warm up crappy mileage by resetting during the drive (depending on when it was reset). The 70MPG should be pretty accurate, 270 miles plus the warm up for starting the drive back would largely make up for not having the first warm up included.
60 mpg(us) at 60 mph is expected. Anything more than very little driving at 80 mph should have dropped the average down fast. BobWilson posted mpg/mph studies a few years back for anyone curious enough to track the PC thread down.
75 mpgUK is achievable with ease. Just keep a steady 50/55 mph on the flat and you'll amaze yourself. Keep it a steady 50 mph on those average speed camera construction zones on the motorway and you'll get 80+mpg UK! I know I have a gen3 but check this shot of my average on the flat at 45 mph stuck behind a truck. The blocks are 5 minute averages and the screen is over 30 mins. You'll be amazed at the mpg's you'll get now the weather is getting warmer.
On flat terrain at moderate 60-70 degree F climate, I can usually achieve 51-53 mpg with cruise set to 70 mph with my 2010 Prius. Terrain and temperature play a significant role. I've reached just shy of 70 mpg averages commuting to work averaging 45 mph speeds with low traffic conditions. Love living in Florida. The Prius was built for a place like this.
75pmg (imp) is very good! I took my winter tyres off yesterday and installed new plugs (at 67k miles) and my mpg instantly went from 50ish to 55 mpg! That was yesterday with temperatures below 5 celsius. Hoping for 60 ish mpg this summer when temps rise. Happy enough with mid 50s though as I am up and down hills here in Dublin
Tony, and David as GC says the high 60's to low 70's are readily achievable in the gen2 on the MFD figures as the weather gets warmer. I recorded on a run of 90 miles with a mixture of rural, town, and motorway roads keeping the speeds at or below 65 MPH 78 MPG from a cold start. However be aware that if you have the OEM size 195/55/16 tyres fitted the MFD calculation is about 3 MPG optimistic. Changing tyre size to 205/55/16 cures this optimism and the MFD then reads virtually spot on compared with millage calculations using fuel added. The larger size of tyre actually has lower rolling resistance than the smaller OEM "make for make of tyre" and does not lower the reported figures and can improve them further with the right choice of tyres. John (Britprius)
First post here... After reading some articles, I've recently radically improved the MPG on our 2007 Prius, although having a new head gasket has probably helped a bit. Up until recently I've used her for short trips - necessitated by her rather alarming thirst for water - and averaged 45-50 mpg (UK). Driving from near Horsham to Guildford on the 'rollercoaster' A281, averaging around 50-60 mph with a bit of time spent stuck behind a slow lorry, over 20 miles I averaged over 80 mpg from a cold start. By the time I got to East Devon, including going through Guildford and up over the Hog's Back, cruising mostly at 60-70 on the A303 I was still at over 70mpg for over 150 miles. I'm running 37/35 psi if that makes a difference and I was trying to 'glide' as much as possible and not to rev too much on the hills. Although the head cost 50% more to fix than the car cost to buy, I'm very impressed with the old girl and she definitely doesn't look or feel her 295,000 miles!
