Need help getting better MPG

[untitledblue]

I'm slightly frustrated since I do not know what I am doing 'wrong' in regards to MPG. A little background info...

I've had my car since March '09. A typical travel to work is 15 miles (there and back home)-that's 5x a week on the highway doing mainly 60-65mph. Weekday I normally stay local or don't drive, but when I do it's normally on the city streets from 20-35mph.

I am currently averaging 36.3mpg. When I try to get better mpg there's always a car up my tail so it's hard to practice (I live in Houston where there's a decent amount of congestion). I've tried to read articles online but it seems too confusing to me. Can someone explain in layman's terms how I can get better mpg? I am about to fill up on gas and start from scratch.

I also kinda got pissed off when I saw this guy:
Pulse and Glide plus Warp Stealth in the Prius II for maximum FE … - CleanMPG Forums

Any tips are much appreciated!

[Vic Doucette]

What tire pressures are you running?

The Prius, IIRC, has a suggested pressure of 35 psi front and 33 psi rear. Many Pris drivers increase that, sometimes quite a bit. I run 40 front/38 rear.

When I added more air, I noticed two immediate effects: An increase in gas milage and an improvement in handling. The car now wallows less and handles more crisply.

I also notice that the traction control system activates more easily, but I have never felt unsafe or in danger of losing control when this happens.

[untitledblue]

Originally Posted by Vic Doucette

What tire pressures are you running?

The Prius, IIRC, has a suggested pressure of 35 psi front and 33 psi rear. Many Pris drivers increase that, sometimes quite a bit. I run 40 front/38 rear.

I accidentally filled them up to 40/35 ('cause I stink at filling up my tires) but didn't see a change in mpg. Right now they are at standard levels since I just came back from my first check up at the dealership.

[JimboK]

Start with this.

Who p***ed you off in the CleanMPG article and why?

Increasing tire pressure above "standard" (i.e., placard) pressures will indeed improve your fuel economy. If you're going to request advice, you might consider heeding it.

[krousdb]

Originally Posted by untitledblue

I also kinda got pissed off when I saw this guy:
Pulse and Glide plus Warp Stealth in the Prius II for maximum FE … - CleanMPG Forums

Any tips are much appreciated!

LOL, that was me that you got pissed off at.
I think the main culprit is your short commute. At 7.5 miles each way, the car barely has time to get warmed up by the time you are at your destination.

[Felt]

Originally Posted by krousdb

I think the main culprit is your short commute. At 7.5 miles each way, the car barely has time to get warmed up by the time you are at your destination.

I am certainly no expert (1900 miles on my G3, IV), but I agree with the above comment. Is the drive to and from work the only time you drive the vehicle? That will be tough!

I suggest you monitor the Hybrid System Indicator (HSI) screen. Make every effort to keep the "ECO" light on. The sliding illuminated bar wants to be to the left of center as much as possible, however, it can go to the right of center, and as long as the ECO light it lit, you will be doing OK. Avoid being all the way to the right .... PWR.
Make every effort to drive steady. Accelerate with the flow, but try to avoid speeding up, changing lanes, slamming on the brakes (I know, I have driven in Houston).

The HSI screen will also give you an indication of how your fuel economy is doing. Once the engine is warm, driving a steady 35-45 mph, the scale should be well over 50 mpg. Then as you get off the accelerator and coast, it should read 100 mpg. At a dead stop, it obviously reads 0 mpg. It's OK for it to read 25 mpg when accelerating, but as you stay with the flow of traffic, it certainly should be well above 50 mpg. You just need to drive sufficient miles in that mode for the average to improve.

Houston is a tough driving environment. My Sister lives there, and I ask her ... why do you live here?

Good luck. I think the Prius requires some time to "learn" how to drive it economically. Go for a Sunday drive down to Galveston. If you drive steady on the Gulf Freeway, you should get 52-53 mpg. Then drive to the West down the seawall drive at 35-45 mph and you will approach 55 mpg. I am convinced it is not necessarily slow driving, but steady driving that is important.

[Shawn Clark]

Houston through summer will be tough on mileage due to AC use and Houston traffic (used to live there.) With a short commute if you have the AC blasting you are going to lose a lot, particularly at low speeds or when stopped. I try to run the AC on low blower settings, and only when I need it. This keeps the ICE off for short stops/at lights. Houston has two advantages: very mild winter, plus it is flat.

I run 42/40 on my pressures, this is within the sidewall rating and seems to work better with the tires than the placard pressure.

City street speeds of sub 35 mph are ideal for pulse and glide IF you don't have to stop or brake alot. You want to keep the car from regenning as much as possible (as it does when you are completely off of the accelerator) as well as avoiding doing extended yellow arrow EV drives. Drive like you don't have brakes, do regular ICE acceleration and learn how to do the "no arrow" glide. While the Prius mpg peaks somewhere around 20 mph that is without the AC on...with the AC I suspect the peak is closer to 30 mph depending on settings.

I change my own oil and use 3 quarts instead of the nearly 4 quarts that Toyota lists (which results in an overfill condition.) Some have observed mpg reduction with the standard Toyota overfill quantity. Have you checked your oil level?

For acceleration the target is instantaneous mpg of ~1/2 of your speed. This gets you into an efficient operating zone. Too low of an acceleration is actually detrimental to mileage, as is flooring it.

Make sure your car tracks true. If it is pulling to one side or another then you will lose gas mileage and need an alignment (free within the first year or so.)

The 7.5 mile commute is better than the 6 mile commute our Prius regularly sees and its getting 54 mpg on the current tank, despite hills, many stops (mostly at the bottom of the hill, arggg), and highway intermixed. At 60-65 mph, you should be seeing about 55-60 mpg while cruising, but on short commutes this will be seriously derated for warm up and initial acceleration.

It takes awhile to break in the car, tires, and driver.

[Vic Doucette]

Originally Posted by untitledblue

I am currently averaging 36.3mpg.

Do you reset the average for each tank? If you don't, it may take a while -- perhaps a long while -- to see any changes.

[untitledblue]

Originally Posted by krousdb

LOL, that was me that you got pissed off at.

Oh crud! Really? I didn't mean pissed as in "pissed" so to speak, more on the lines of aspiration (it's a compliment).

As for the tires, you guys are probably right. Last time I did it it was my first time-I was completely incompetent and they were uneven so that's most likely why there wasn't much change.

[krousdb]

Originally Posted by untitledblue

Oh crud! Really? I didn't mean pissed as in "pissed" so to speak, more on the lines of aspiration (it's a compliment).

No problem, I took it as such.