Are people really getting 40+ MPG in Gen 2?

A person could hyperventilate there!!

 

2007 bought in July 2017 with 175K miles on it. Fuely numbers in my signature are average since the first time I filled up this car. That includes the winter we just survived, which lowered the average significantly. I just turned over 190K mile mark on the clock. Still getting mid-40' to upper 40's in the summer. I did do a battery reconditioning with the Prolong system in October, but the fuel economy did not seem to be effected by it.

I believe the OP has an issue. It may be the battery art this point, but I would stop idling to begin with. Idling in these cars really draws down the battery even when not doing much. Then the engine needs to come on way more. It's not a good idea to idle for fuel economy, IMO.

I would also look into spark coils and other things related to the engine. Something is off, for sure.

 

2009 120k 44.1mpg original battery

 

I recently bought an '07 with 250k miles. I am getting 39-41 MPG, but I understand this is because I only take short trips so far (the engine wastes more fuel on short trips because it has to warm up each time & less time is spent per trip on electric).

 

Also, the engine is less fuel efficient before it's warmed up. Just like any gas engine.

 

I’ve been working on my hypermiling and towing in my ‘07. I think I could probably hit the original EPA estimate of 60mpg if I didn’t have those pesky mountains to drive over on my way to work!

 

That's looking REALLY good for pulling that trailer over mountains.

 

I've only had my Prius (2008 - 120,000Miles) for 4 days and so far have had an average of 55.7(UK) MPG (I think that's around 46MPG Us?) over 3 trips totaling 80Miles.
That is in and around the very hilly landscape of Wales, half was 70mph Motorway and the other half 30mph town driving and traffic jams.

I am trying my best to learn P&G and also getting to grips with 'coasting' at motorway speeds (only the battery arrows showing) but practice will make perfect.

I haven't even checked the tyre pressures yet! So this could be improved upon! I am amazed by the Prius and blows my old VW TDI out of the water in terms of efficiency and easy driving!

 

I find that the difference between "just drive it" mode, where I simply turn off the MFD screen and drive my '07 (with 190K miles) and when I do all my P&G technique and other things trying really hard to get the best score on the MFD video-game is only at most 5mpg (US). This doesn't mean I don't try to drive "economically", but it's just a small difference and it's worth knowing what it is for you as an individula. Some people have way more patience and skill at this and their difference may be greater, but for me, it's sometimes worth it to "just drive it". I live in the countryside with gentle rolling hills here and there and big valleys with level grade, so my everyday driving is economical as it is, it seems. I do make highway trips to Boston (about 90 miles on the highway) and highway is really a gas mileage killer for me as I simply can not go slower than 75 and stay awake, so I use my cruise control, which is also mileage killer from what I hear, and it still does well. Winter weather for me is much worse in terms of mileage than driving style. My numbers have dipped to high 30's in some of the coldest days. But my average is still in mid-40's and that's since the first time I filled this car up last July.

 

Driving with some attention, high mileages (>50 mpg) are possible.
But driving several hours with maximum speed (112 mph speedometer/ 106 mph GPS), the mileage drops below 30 mpg.

 

I just put this on another thread, but I think it fits here perfectly, too. It's a screenshot from when my wife filled up her '07 yesterday. She is not an aggressive driver at all, but she also doesn't try to hypermile. It shouldn't be hard to get 40+ in a Gen 2 if it's not broken in some way and you're not driving it like the typical SUV driver or have some special driving situation that makes it work harder.

 

It has been my experience that if a car has a built in MPG/fuel per trip indicator, the accuracy drops if there is a long term fuel trim that isn't 0. So if the LTFT is -5 or +5, fuel accuracy may be affected by that same percentage. LTFT can be affected by a variety of things such as a dirty/old Oxygen sensor or perhaps a vacuum leak, dirty MAF or any number of things.



As for OP with the fuel economy problem, at the very least he should replace his PCV valve and check on how his oil consumption is doing on a rolling 5K mile basis. Depending on how bad the oil consumption is, these cars start to plug up the catalytic converter which hurts efficiency as well. If the OP's car is in a very hot area, his excessive A/C usage and or the very hot battery could be negatively impacting the fuel economy. On an older, weak battery, the car may be eager not to use the battery pack but instead prefer to use the engine instead.

 

GOOD FOR YOU I have been away from this forum for over 2+ years due to fighting an illness. I was once known as OCD4aPRIUS (or something close to that. On my wife's birthday July 24 2012, we bought a 2007 from Earl Stewart in West Palm Beach....He (I'm referring to 'the MACHINE" now, had 57K. He now has 145+. I get my oil changed @ the dealership I bought him from & I get FREE TIREs for LIFE. NOW i'M LOOKING TO TURN HIM INTO A CAMPER, which is why I'm back.

As far as mileage goes I firmly believe in the techniques I learned HERE since 2006 when we 1st rented 1 while in Conn. It was LOVE @ FIRST FILLUP !! i'VE LEARNED WHERE HIS 'SWEET SPOT IS." I won;t go into all the details yet how a person drives--never rush to a red light--that determines MPGs. When r people going to REALIZE THAT F-A-C-T. My 145k+ still gets 48-54MPG. Ok, I did 80 down 95 and only got 44mpg ( I was late for the oil change).

Use GOOD GAS-CHEEP GAS will screw up your machine no matter how you drive. I have the best MPGs w/ 1)Chevron; Mobil; Sunoco in a pinch. In short I have a LOVE Affair W/ MY PRIUS GEN 2-YEA, IT CAME W/ ALL THE BELLS ....I think it's called level 5 or something. I still haven't had time to learn the GPS LoL. My wife Karen still teases me. That's OK. I keep her washed & waxed, change the oil, filters i do myself; wiper blades--then we rock & roll anywhere we care to go. Thanks for listening, I mean reading. This was the BEST investment of my lifetime,

Sincerely,

Don Taylor

 

Bout my 07 at 279k MFD was still showing an avg 50.5 with AC inop
I fixed the AC and drive around like an icebox...still getting 40-42 REAL WORLD MPG in 95°+ SC weather with 285k original HV

 

I just had to refuel for the first time in my 121,000 mile (both original battery's) 2008 Prius. (35psi tyres)

I got 493 miles until my last pip was lit and an indicated 54.8 UK mpg (45.6 US) on the computer.
When I did the math it worked out as 54.1mpg (UK) so I'm very happy!

My old VW Bora (jetta) Tdi used to get 46mpg (UK) and diesel is more expensive here.
Not to mention I pay less tax (£10 instead of £140 a year) my insurance is £30 cheaper a year so I'll be saving a good chunk of change each month, which is just as well since I have a 5month old baby!

I plan on upping my tyre pressure to 37psi to see if that helps, unfortunately I have cheapy non-brand tyres on at the moment, not LRR tyres. so when they need changing I may splash out and get LRR.

 

My Gen 2 was starting to slip on gas mileage at over 100,000 miles.

 

Are you using 95 octane petrol? If you use 98/99 you should try a couple of tanks of 95. No point paying more for petrol for no benefit.

Also, as far as tyre pressure goes, more is not better, in this case. There is a diminishing return using anything higher than 37 PSI front/35 PSI rear and what you gain in marginally higher MPG, you will loose by having to replace your tyres prematurely, due to the tyres wearing out in the centres. Keep an eye on the tread depths over the whole width, taking measurements with a tread-depth tool – inside, centre, outside. Record your measurements for each tyre. It is not easy to visually spot 0.3 - 0.4 mm difference between the centres and the outsides, but will become obvious when you measure.

Food for thought. YMMV.

 

BTW, the price doesn't have anything to do with the quality of the gas
I know raceway stations that are the most expensive I the corner, and it is definitely "cheap gas"

Go HERE! That will tell you where to get your gas...

 

Not much help to someone in the UK. Petrol there is pretty much 2 tier and locals (that care) know which to use and avoid. Some use the cheapest in any case.

Also they RON in the UK as opposed to AKI used in the US, so 95 RON = 91 AKI and 98 RON = 93 AKI.

 

2005 w/175,000mi — 42mpg

Was told the drop from 51 might be the oxygen sensors.