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So I just barely filled up like half an hour ago, and for this last tank I got an average of 22.34 MPG. The Camry is rated at 22 city and 30 highway with the four-speed automatic and 130-horsepower inline-4. I drove 283.7 miles using 12.701 gallons of gas. It would actually have 133 horsepower but Vermont follows the same emissions guidelines/restrictions as Calfornia, thus the Camry has a "cleaner" version of the engine.

The Scangauge II is really, really close to the hand-calculated average. I think it's only a couple of tenths off, so I'm getting pretty good at this.

About 160 miles out of the 283.7 was driving to Burlington, VT from Middlebury, VT (40 miles each way, two round trips). In both cases I exceeded the highway estimates, a couple of times getting up to 36 MPG.

Here's why I think my fuel economy has improved so much:

1) Instead of directly driving to school and/or taking my mother to work (both places pretty close to home), we usually leave about twenty minutes
early to drive the Camry around to fully warm it up. Because of this, we've been taking roads we've never been on before, and we have actually learned more about the town we live in than we used to (what roads lead to where, what streets are called what, etc.) In fact, just tonight, I was able to achieve 25 MPG just driving a few extra miles to fully warm up the car.

2) I keep staring at the instant MPG gauge. I'm amazed at how easily I can keep the car at a set speed and still have it read 30, 40, even 120 MPG depending on if I'm on a flat road, going down a slight hill, or going down a steep hill. It can easily hit 100 MPG at 30 MPH on a slight downhill road when the car's fully warmed up.

3) I have experimented as to what improves fuel economy; accelerating to speed quickly and then maintaining the speed by slightly pressing the pedal, or gradually getting to speed. Other things include using headlights versus only DRLs (haven't noticed a difference, if any), taking roads that have more stop signs than stop lights (those lights take so long to turn green), driving to the furthest destination first instead of the closest one first, never exceeding 2000 RPM around town...

4) Avoiding as many "gas-killing obstacles" as possible. I am so aware of the town's layout now that I'll actually avoid certain roads because of a steep hill or other similar obstacle that can quickly "kill" gas mileage. If I've just started the car, I'll avoid steep hills like the plague, but if it's fully warmed up and I've driven for a while, then it's easier to stomach because it won't affect the overall MPG by much.

This has turned too much into a game, and I love it. :D

I was able to achieve 25 MPG just driving a few extra miles to fully warm up the car.

While this is very commendable, Unless the amount of fuel used is less than would would be used without driving the extra warm up miles, it isn't realy doing anything for your pocket book or the environment. Use this calculation to find out fuel used: Miles driven divided by Fuel economy. I think that is the correct calculation. Ideally you want any new routes or warm ups to be less than your old route.

One thing you can also do is to get to a set top speed around the speed limit and allow yourself to slowly decelerate to a minimum speed you feel safe at and then accelerate up to the top speed and repeat. This will optimize the amount of time you are getting 100+ mpg.

Tom is right. It's unfortunate, but sometimes we all have to sacrifice the numbers in order to burn less fuel overall. It's very important to take that into account first, and the gas mileage numbers second.

Did you ever look into an engine block heater? I still think that's the best way to improve your short-trip mileage and emissions.

How about the cost of electricity for the block heater vs. the gas extra gas that would be used for a conventional warmup? Is the block heater the hands-down winner?

I don't know if it's a hands-down winner overall. It depends on the cost of electricity, cost of fuel, and impact on a specific car's fuel economy. I think it's a hands-down winner in terms of emissions, as the electricity used to heat the engine is going to be cleaner than an engine running rich and cold for an extended period of time. Even if it's from a coal plant. In terms of overall power, that can be minimized by setting it up on a timer to turn on an hour or two before you plan to leave in the morning.

Tbaleno,

Firstly thanks for the info. I'm concerned about overall fuel used, yes, but I'm more concerned about making sure the car is fully warmed up. It can be hard on an engine if it's only being driven cold. Plus Mom and I enjoy the rides; it's not like we have to do it. :)

And that technique you mentioned... that's more or less a "non hybrid" version of pulse & glide, right?