My last two posts have been quite lengthy... I just get carried away talking about cars, and I want to be as informative as possible!  In an attempt to reduce the size of my posts, I will make an effort to post more frequently, and potentially divide blogs into parts if necessary. 

I would really love to hear from you - tell me about topics you'd like to read more about, or questions that you'd like to have answered!  I'm here for you!!!!!

With fluctuating fuel prices and a general interest of the general public to be more environmentally conscientious, it seems as though fuel economy is often a major consideration for those looking to buy a new or used car!  but how can you do your homework before going dealer to dealer? 

The most comprehensive and easy to access resource is called the fuel economy guide.  It's published annually by Clean Cities, an entity withing the US Department of Energy.  Each guide lists every vehicle sold in the United States for a given model year, along with details about the engine type, transmission type, and fuel economy.  The list is arranged by vehicle size (midsize car, full size truck, etc.), and also by powertrain (diesel, hybrid, electric vehicle, etc.).  You can find fuel economy guides for each model year, as early as 1984.  The most recent is the fuel economy guide for 2010.

I think it's worth taking a few minutes to describe what fuel economy actually means.  From my experience, most people are familiar with the mile per gallon (mpg) terminology, which describes how many miles a vehicle can be drive on one gallon of gasoline.  So how are a vehicle's mpg numbers determined?

The federal government has described drive cycles for city-type driving as well as highway driving.  This is why people refer to mpg values for city and/or highway - they are quite different.  (For vehicles with conventional powertrains, in city mpg's are lower than highway mpgs.  But for vehicles with batteries, such as hybrids, the opposite trend is true... since a battery enables one to recover energy lost by braking (called regenerative braking), hybrids have an advantage from a fuel economy perspective compared to non-hybrid vehicles in the city, and the mpg for a hybrid is lower on the highway than in the city.) 

So what is a drive cycle?  First, the purpose of a drive cylce is to enable consumers to compare vehicles on an apple to apple basis.  Every modern vehicle sold in the US is mandated to "certify" according to the city and highway drive cycles, and hence the mpg's reported allow consumers to compare the numbers from one vehicle to another, knowing that they are truly comparable.  The city drive cycle is shown in the plot below, and is referred to as the FTP city cycle (FTP = federal test procedure).

The highway drive cycle is shown in the figure below. 

Why are drive cycles important?  Well, depending on how you drive your car or truck, you will burn more or less fuel.  One example is how you drive in stop and go traffic - if you are hard on the pedal when accelerating and hard on the brakes at each stop, you will burn more fuel than if you drive according to the FTP city drive cycle.  This is because you are "loading" the engine more... the more that you step on the pedal, the more air that enters the engine (the combustion chamber), and because the proportion of air and fuel is basically consistent at all engine operating points (it's always approximately at stoichiometric air/fuel proportions).  Another example is driving up long hills - if you live in a place like Pittsburgh, for example, you drive up a lot of hills.  It takes more energy to propel the vehicle up a hill, even if you are traveling at a moderate speed (40-55 MPH), than if driving on a flat surface, and hence you consume more fuel (fuel provides the energy, of course, for a conventional vehicle, meaning a vehicle without a hybrid battery). 

Do you have other resources that you use for learning about fuel economy?  If so, please share them!  Do you have questions about fuel economy, drive cycles, or anything else discussed in this blog?  Please let me know!!!

While in graduate school I had the opportunity to do a few week-long workshops with high school students.  I researched combustion in an engine lab at Penn State, so for the said workshops I'd have a group of 6-10 girls learn about the internal combustion engine (ICE), specifically spark-ignited (gasoline) engines, set up an experiment, run it, analyze the data, and present the results (this was a part of an annual summer camp sponsored by Women in Science and Engineering called WISE Camp, so many groups of students presented their project's findings at an end-of-camp assembly). 

The opportunity to work with high school-aged females on a topic that is typically male-dominated was really fun!!  I was always proud at how empowered the girls felt when they learned about combustion and realized they had potential to understand it just as well as (if not better than) any guy could!  And while talking to these young girls about everything from combustion to college to life, it occurred to me just how limiting our socialization, as females, can be.  This realization isn't profound, of course.  However, having been involved with automotive related projects and careers since I was 19 years old puts me in a "not-typical" category of women.  And I simply wanted to be able to bring some more girls over to my side!!!

One of the things I devised was a list of "10 things all women should be able to do" related to cars.  Here it is:

1. Change your engine oil
2. Drive a manual trans
3. Change a flat tire  
4. Avoid getting duped at the service station
5. Shop for a car without getting the run around
6. Know how to top off your fluids
7. Change fuses
8. Jump start
9. Change wiper blades
10. Change your air filter

I've already blogged about changing a flat tire.  I'll dedicate the next 9 blogs (including this one) to the remaining items on this list!

So now the question becomes, what is your preference for shifting gears?  Can you drive a car with a manual transmission (stick shift), or do you prefer an automatic trans?  I always offer that you never know when you may end up in a predicament where it would be useful for you to be able to drive a manual (i.e. taking your drunk friend home from the bar in their car). 

Here are a few tips for those of you who want to learn to drive a stick:

1. Find a car with a manual trans.  Probably good to get a patient friend to spend a few hours with you some Sunday afternoon :) 
2. Find a nice, flat, empty parking lot - this will be the best place to start your education. 
3. Take as much time as you need!  Spend some time getting used the clutch.  Push in the clutch (disengage it) and put it into first gear, slowly let the clutch out (engage the clutch) until the car barely inches forward, and then push the clutch back in until the car moves backwards slightly.  Do it over and over again.  Notice the point on the tachometer (the RPM meter in the dash) where the engine RPM's decrease slightly as you let the clutch out - this shows that you've disengaged the clutch, and that you can give it some gas and go!
4. Practice!  Once you've grown comfortable with the clutch, take a drive around the parking lot.  Practice driving, stopping, shifting from neutral to 1st and to 2nd if you have enough space to get your speed up a bit.  Once you understand how it works and can manipulate the trans, it's truly just a matter of learning a new habit.  Your feet and right hand have to learn a new routine in order to respond smoothly. 
5. After you're good and comfortable, the next step is to take a drive on a not-so-busy street.  Side streets in a downtown (not during rush hour) is a good place to start.
6. Hills are the next best thing to practice, but only once you've gained some confidence in stop and go situations.  The most important thing to remember is that when you disengage the clutch (when you push it in), your gears are not engaged (you are essentially in neutral).  When on a hill, keep your right foot on the break, and your left foot on the clutch.  Make sure you're in first gear.  Watch the tachometer, and let the clutch out slowly until you see the RPM's drop slightly.  At that point, give it some gas, and be generous!!

A few things to remember as you become accustomed to driving a stick:

• Don't panic!  Stalling, while frustrating, is no big deal.  Just put your foot on the brake, start the car again (in modern cars you have to remove the key from the ignition before you can start the engine again).  
• When in doubt, push in the clutch!!
• If you get confused about which gear you're in, just put it back into neutral and select the appropriate gear. 
• Downshifting takes some time to get used to, especially in terms of when to downshift.  So just practice until you get good.  You'll learn the vehicle and typically become accustomed to the sound of the engine as a cue.

If you'd like to know what's so great about a manual trans, check out this article at Edmund's.

 If you end up getting behind the wheel of a car with a manual trans, let me know how you do!

Have you noticed a slight slump in your fuel economy lately?  Needing to fill up a bit more frequently than usual?  We're approaching the time of year (in the NorthEast, at least) where cooler temperatures may lead to lower tire pressure.  Did you know that proper tire pressure, not to mention good tires, is a key component of maximizing miles traveled per gallon of fuel (mpg)?  If not, now you do!

How do you know the pressure in your tires, or where to determine what the pressure SHOULD be?  First thing's first - find a tire pressure gauge!  It's good to keep one handy in your car, but you can also find them at the air-fill center at most fueling stations.  If you have your own compressor, you'll definitely want your very own gauge!  You can get simple, inexpensive mechanical ones, or fancy digital gadgets.  Either kind will do!

So how much air pressure is appropriate for your tires anyway?  You can check 1 of 4 places to find that answer:

• The label inside the door jamb (driver side) of modern vehicles
• Vehicle owner's manual
• Raised lettering/numbers on the tire itself
• The interweb, of course - though I recommend the other three unless the manufacturer's website contains such information, but even in that case many vehicles have multiple options so you'll have to be dilligent about acknowledging the accessory packages on your vehicle.

Once you're in the know you can top off the air in your tires!  Be careful not to overfill, of course.  If the hose you use for filling has an integrated pressure gauge then you should be fine.  Otherwise, take the time to pause, employ the gauge, and fill more if necessary!  **Tip: I recommend removing all valve stem covers and placing them in your pocket before starting - it's easy to lose those little buggers!

A few other things to check if you're using more fuel than seems normal (many of these should be updated on a regular maintenance schedule, and for good reason!):

• Engine intake air filter (you can change this yourself - refer to the user's manual and buy one at the local auto parts store!!)
• Oil change (are you up to date??)
• Spark plugs/wires
• Fuel filter (especially for older vehicles)
• Try a bottle of fuel injection cleaner, assuming that your vehicle has fuel injectors instead of a carburetor (vehicles of vintage mid-70's on should have fuel injectors)
• Top off all vehicle fluids, as necessary
• Your driving style and/or commute (I'll blog more about this topic next time!)

If you're not sure how to check these or how to know if it's time to worry about them, refer to the maintenance schedule in your owner's manual - it's a pretty useful tool, that owner's manual! 

Happy driving!!!

Image c/o lanier67So you're in the middle of an interstate at 8PM on a Sunday evening and you drive over something small and inconspicuous, practically unnoticeable except you're left feeling a bit of a tug in the steering... something feels strange. Could it be a flat tire? First thing's first – don't panic!! Simply employ a few helpful tips and you'll be back on the road in no time!

1. Pull off of the road so that you can verify the flat

2. Which tire is it? If it's a driver side tire and you've pulled off onto the right shoulder then I suggest finding a more open area to work in (SAFETY FIRST! While you can damage the wheel if you drive too long on a flat, and should do so only as a last resort, ensure your safety before all else).

3. Time to get the tools. Hopefully you have a true spare tire or a donut along with a jack, lug nut wrench, and if you're unfamiliar with changing tires you should grab your owner's manual as well.

-The tools should be in your trunk, typically in a compartment beneath the floor, along with the spare.

-I recommend that you carry an old bath towel or blanket with you at all times – it will come in handy for side-of-the-road vehicle repairs.

-If you do not have any form of a spare, or fix-a-flat, then you'll need to call for help.

4. Loosen the lug nuts (this may require a little muscle, so give it all you've got!) – this should be done before raising the car with the jack. Remember, lefty loosey, righty tighty. You'll want to turn the nuts counter clockwise in order to loosen them. Do not remove them yet – the objective is to crack them open on the ground so that you don't apply too much force when the car is up on the jack (prevent damage to vehicle and to yourself).

5. Position the jack beneath a structural point just inside of the wheel (refer to manual if necessary). You may want to place the towel on the ground for comfort and to eliminate getting dirty when placing the jack. Raise vehicle until the tire is above the pavement.

6. Remove the lug nuts completely – place them in a safe spot! (pocket, pile in the trunk)

7. Remove the tire – might take some muscle but you can do it! You'll want to take it home with you so that you can have it repaired (do not throw it away – even if the tire is destroyed you want the wheel!)

8. Position the spare tire (you're almost done!)

9. Replace the lug nuts finger tight. Lower the vehicle and remove the jack. Now finish tightening the lug nuts - torque those bolts as tight as you can!!! 

There you have it - you changed your OWN flat tire!

Let me know how it goes!

Any other car questions? Contact GG and let us know!