only 36-37 average mpg?

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

and post your answers as a reply here. This will provide a lot more clues to help us give feedback. Based on your previous posts, it appears that the 12V battery is not likely contributing to your shortfall.

200 miles isn't usually enough to learn how to drive a hybrid. Did you reset the Trip meter when you bought the car, so that it is showing only your results, not mixed with the performance of the previous owner? Resetting it each morning will help provide faster feedback about how you are doing, and really highlights the mpg penalty of short trips on cold starts. (This penalty applies to non-hybrids too, only electrics escape it.)

You don't need to use N much or at all, except as a training aide to learn what a real glide is.

 

I second fuzzy1's comments and add mine:
What type of tires do you have? How much air is in them? What is the oil level?
Non LRR tires and overfilling the oil (and/or using the wrong type oil) can cause MPG in the 30's. I had this problem with the wife's 2008 Prius and JifyLube service.
I suggest you not try to out-smart the car. Don't ever shift to neutral - you need to allow the car to use re-gen to charge the battery. Otherwise, the ICE will run to keep up the charge on the HV battery.

 

What they said

Tire pressure ABSOLUTELY, get OCD about it. You don't have to go to sidewall cold tire pressure but if they are below the numbers on the door, pump them up. Depending on the tires, they can get squirrely at higher pressures so watch for that and bring them down if necessary. ALWAYS check and fill WHEN THE CAR HAS NOT BEEN DRIVEN for an hour or more. Otherwise, they are NOT "Cold" and you will under inflate them. And, since we are going into "cold weather time" make sure you keep checking them weekly unless you live somewhere lie Phoenix where the temps won't be dropping a lot through the next few months.

Make sure the oil level is in the right range. Make sure the parking brake isn't sticking. That isn't a common problem as far as I know, but it it is, you aren't doing your MPG any favors.

If the spark plugs haven't been changed, it is time (150K for Cal Emission states, 120K for others. This makes no sense since the cars are the same no matter what state they were sold in). I don't know if inverter coolant would affect MPG and there isn't anything in the service manual about changing it. I had it done at 100K because blowing the inverter would be a really expensive proposition.

Neutral - no good unless you want to push the car. Learn to "glide". Basic principle: get a couple of MPH over your desired speed and then let up on the gas JUST ENOUGH. There must be a little pressure. You will learn to feel when it happens. You can't just look at the display and say "Oh 99 MPG, must be gliding" since it will do that if your foot is not pushing enough. Don't try to glide up hill, you'll just lose speed and have to "pay" with gas to get it back. This it the exact opposite of what you want. I don't do "pulse and glide" but where there is down slope or I'm coming to a red light I will glide whenever possible. My 17 Y/O knew about glide and she figured out how to do it without me telling her the above instructions.

You will find hills with just enough slope that you can hold speed and use no power while generating no power. This is good because while recapturing energy when you need to slow is good, there are losses in the process. A distance done with zero power used or generated is better.

Like xpcman said, don't try to outsmart the car just yet. If you can use the cruise control, do so. It isn't good on rolling hills because it will lose speed going up, but not figure it out until you crest and are already gaining speed, then it will over compensate. One would think that BY NOW, CCs would be reading like 50 times a second and the driver wouldn't even know it was adjusting. And if you can use it on the Interstate, by all means do so. And recognize that 55 MPH gets WAY better MPG than 65 which is WAY better than 75 MPH.

Also, the noise not long after shutting the car down is likely the pump moving some coolant to the "thermos". It pumps it back when you start the car the next time so there is warm coolant in the block.

My'04 with 131K miles was totaled last week. My last tank was 59 MPG which is in my normal range for summer. BUT how and where you drive is really important. My wife is usually in the low 50's but she drives different roads. My sister lives in So. Cal and can't get over 45 MPG - too much traffic and you ALWAYS stop at red lights because if you leave room between you and the cars in front as you see the light 1/4 mile ahaead turn yellow to NOT have to stop, someone(s) will fill that space. Her battery display is frequently in the green because she HAS to use the brakes so much.

 

What previous maintenance was done? If you don't know if something was done, assume it wasn't ! Areas to inspect: Air Filter , oil, inverter coolant, and pump. Air in coolant pump? Condition of 12V battery, spark plugs. AC filter, cleanliness of air throat. Al of these checks and maintenance procedures can be found on Priuschat: USE SEARCH.

 

I thought of another:
ABSOLUTELY DO NOT think you can get good MPG by crawling up to speed on the electric motor. Basic physics, it takes more energy to get a body moving than to keep it moving. Let the car use the gas engine to get up to speed as it sees fit, it might even be charging the battery at the same time if you aren't lead footed. Then, once up to speed, the car will use the electric motor as it sees fit. The lower the state of charge, the less likely you will go into electric. Thus, using the battery to get to speed makes it LESS likely you'll use electric when it is most helpful, MPG wise. The only time this doesn't apply is if you are going (or will be in a SHORT distance) down hill where the car will not need much fuel from either source to maintain speed. There are a lot of calculations going on all the time. Battery SOC, "power" request, etc. You might do well to have someone else (preferably a knowledgeable Prius driver) drive while you sit and watch the displays.

Oh, and ANOTHER one At first I thought it would be good to end up at home with lower battery SOC (not 2 bars low!) because the engine would run in the morning anyway and would charge the battery. BUT, what I didn't realize for some time is that the computers baby the gas engine when you first start the car by having the electric motor take most of the load while the ICE warms up. BUT it can't do that if there isn't a decent SOC (4 to 6 bars). I finally noticed this because I live at the bottom of a hill and the battery bars would drop faster going up the hill on a morning start than if I came home then went back out while the engine as still warm. I think a properly maintained Prius ICE will last years and years longer than the ICE in other cars. It doesn't run when the car isn't moving; it isn't always running when you ARE moving, even at speeds above ~42 when it has to rotate but doesn't need to fire; it isn't doing "hard wear" cold starts unless you live somewhere you HAVE to use it hard before it warms up) e.g. on or very near a high speed road).

Oh to have a 'mini plug in' where we could top off the traction battery to whatever is "full" so there would be 8 bars (assuming you don't live at the TOP of a hill) of electricity available in the morning. Then I could electric more on the way home.

 

Good questions. The service manual says nothing about changing the inverter coolant. I had mine done at ~100K on the '04 "just because". At 147K, the OPs car is about due for new spark plugs if they weren't replaced at 120K - the interval for non California emissions states. Since the cars are EXACTLY the same, no matter what state you buy it, I have no idea why Toyota says 120K for the other states.

Just noticed this in the OPs post: "147k car mileage reduced its average mpg."
The WORST MPG I got in my '04 this summer was a 1200 mile round trip in early June that included a fair amount of 65 MPH interstate. Just over 50 MPG. EVERY tank from then until it was totaled were over 55 MPG, 2 were just over 60 MPG. So I would say "No, higher mileage cars are not destined to get worse mileage". In fact, I haven't managed to get my "new" '09 with 42K miles above 54 MPG. But then it is getting colder and that takes a big toll.

Bruce

 

You shouldn't put the car in neutral ever. It will not regerate power to the traction battery in neutral, only in gear. So while you may move downhill faster, you are not harnessing any of that energy. That might be killing you.

 

#1 Rule of n00b Prius ownership: Drive it like any other car.

After you see what the car does, then you can try and improve upon it.

 

These are the things that stick out to me. 35PSI is pretty low. Bump that up. You don't have snow, so don't worry about it.

Stopping and going with trying to stay in electric mode will combine to create horrible mileage. Do NOT try and drive in electric only mode. It is wasteful and the least efficient operational mode the Prius has without a plug to the wall. Drive it like a normal car with easy braking for a few days (with a reset mpg meter) and see what happens.

The car "creeps" like a normal automatic transmission vehicle, except the Prius does it just to make it feel like a normal car, there is no reason for it to do so. When you stop, you need to actually press the pedal in so that the creep stops. Otherwise you are just burning away energy. When you press the pedal hard enough the electric motor stops trying to move the car, so there is no waste there. Hold the brake so the screen is clear.

And you seem to be confused about the system. The battery bar on the MFD is the traction battery, not the 12v battery.

 

13.9 is impossible. That's the wrong value. Tell us the 3 values you see.

35 psi is too low. I'd run at least 38 front and 36 rear. And yes, Goodyear Integrity tires are crap. I don't have mine anymore. When replacing them, do get LRR tires. See Low Rolling Resistance replacement tires: Current List | PriusChat.

As for trying to stay in electric, if possible: DON'T do that unless you're creeping along in stop and go traffic or at parking lot speeds. If you're going to accelerate to even 25 mph, don't baby it, let the engine come on.

As for warm up. Don't do it! 0 seconds.

Your short trips (e.g. 5 miles) will kill your mileage, esp. if they're city and have lots of stopping/stop and go. Most fuel-efficient cars shows what CR got. Last page of http://www.consumersunion.org/Oct_CR_Fuel_Economy.pdf describes their test vs. old EPA test.

 

for me, the first number is 11.9, seems a bit low.

 

And what are the 2nd and 3rd values?

 

Yeah 11.9 is low.



If its the original battery in your 2007 Prius, its time for a new one as that one is 5-6 years old and reaching the end (or has reached) of its service life.

 

Have you changed your spark plugs??? i don't think is talked about much and I only signed into this forum and priuschat to let owners know. I have a 2007 and I just hit 120,000 miles. I purchased it with 18,000 miles on it and the maint manual says to change the plugs at 120,000. When I first purchased the car I was getting 36-39 mpg and I thought it was normal because people were reporting a wide range depending on how they drove the car.

Well after 100,000 more miles I changed the plugs today with Bosch Iridium ($36 total) with $16 mail in rebate. I went from 40.2 mpg (recently) --- for some reason my mpg's got better over the years to 50.6 mpg on my 36 mile commute home. This is over 10 mpg difference with no change in how I drive. Not only is the car running smoother but you can tell the engines are working in better unison.

 

Stop putting it in N your wasting some energy that should be harvested by the Regen system, let it use that inertia to recharge the battery as you coast or slow down. Use the brakes lightly as you slow to a stop as you can put a good deal of energy back in the bank when done correctly. Don't pull away from a stop like your in a funeral procession, Accelerate fairly briskly and then "soft pedal" it at speed so the computer can work its magic. Make sure the tires are not low....IMHO you should drive it for a while and let the car try to teach you how to get better mileage before spending money at the dealer. I would have little faith in a dealer that did not mention not to try and use N to get better mileage.

RAL