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Fuel Efficiency Adviser review: Fuel Efficiency Adviser

Fuel Efficiency Adviser

Wayne Cunningham Managing Editor / Roadshow
Wayne Cunningham reviews cars and writes about automotive technology for CNET's Roadshow. Prior to the automotive beat, he covered spyware, Web building technologies, and computer hardware. He began covering technology and the Web in 1994 as an editor of The Net magazine.
Wayne Cunningham
3 min read

A typical car's trip computer shows information like average miles per gallon, range to empty, and distance traveled, but if you want to know more about your car's performance--a lot more--then the Fuel Efficiency Adviser deserves a place on your dashboard. Billed as a device to help you drive more frugally, the Fuel Efficiency Adviser overwhelms with an incredible amount of data, everything from instant miles per gallon all the way to manifold pressure.


Fuel Efficiency Adviser

The Good

The Fuel Efficiency Adviser serves up loads of data about your car. It is highly programmable and also displays and clears engine error codes.

The Bad

The device doesn't offer any actual tips on driving more efficiently, requiring you to interpret the data. Some cars have trip computers that replicate many of the Fuel Efficiency Adviser's functions.

The Bottom Line

For serious car geeks with an engineering bent, the Fuel Efficiency Adviser will provide a satisfying array of data, but others will be overwhelmed by the complexity.

Unlike the PLX Kiwi, which uses colorful graphics to indicate efficient driving, the Fuel Efficiency Adviser provides the kind of data that only an engineer could love. But along with that data comes a great degree of programmability. And even better, the device can be used to check and clear a car's error codes.

A rather simple plastic box dominated by a monochrome LCD screen on the front, the Fuel Efficiency Adviser looks as utilitarian as its functions. It is fairly small, only about 6 inches long, and could sit low on a car's stack, below the stereo and climate controls, where it would be unobtrusive.

More difficult to hide will be its cable, which plugs into a car's ODB II port, usually found under the dashboard near the center. Fortunately, Fuel Efficiency Centers, the company that produces the Fuel Efficiency Adviser, included plugs on the side and back of the device, giving you some flexibility for how you attach it to a car.

The front of the device has five buttons, just simple white studs, all unlabeled. Four are soft buttons, their functions changing depending on what the LCD is showing, while the fifth, in the lower right, is a menu button that will take you back to the Fuel Efficiency Adviser's home screen. The various data or menu items shown on the screen are all easy to read, although many of the abbreviations require you to read the manual to understand.

The Fuel Efficiency Adviser reads and displays data from your car's engine management computer, which is transmitted through the OBD II port. It also lets you program in some data, such as your cost per gallon of gas. Data from the user and from the car is used by the device to calculate items like your current trip cost.

The Fuel Efficiency Adviser shows information from the throttle position (TPS) to current trip cost (CTC).

For the fuel consumption and speed readings, drawn from the car, the Fuel Efficiency Adviser can display data in English or metric units, letting you, for example, switch from miles per gallon to liters per 100 kilometers. Other data it reads from the car includes battery voltage, engine speed manifold pressure, ignition timing, coolant temperature, and intake air temperature.

It lets you enter configuration information to more accurately reflect your car. For fuel type, you can enter gas, diesel, hybrid, and even propane. If your car doesn't report its engine displacement through the OBD II port, you can manually set it. You can also set your fuel tank size, and fine-tune speed, which might not be reporting correctly if you have larger tires than stock, for example.

With the Fuel Efficiency Adviser properly configured for your vehicle, it can calculate trip information such as average miles per gallon and range to empty. It can also show how much it has cost you to drive during your current trip.

Finally, the device has some advanced features. It lets you program in your own commands and it will display engine error codes and clear them. This last feature is particularly useful if your car shows a check engine light, as the error code will give you a better idea of what is wrong with the car.

By itself, the Fuel Efficiency Adviser won't improve your fuel economy. You need to take the data it gives you and moderate your driving appropriately. Its most useful tool for that is the instant miles per gallon reading, a feature that few cars get from the factory.

Installed in a test car, we found that the data it served up is accurate. We also like the different displays it can show from a simple average miles per gallon readout to four different data points, such as instant fuel economy, engine speed, trip cost, and car speed.

Unlike the PLX Kiwi, the Fuel Efficiency Adviser doesn't offer any direct advice on getting better average fuel economy--you have to divine that based on how the instant fuel economy reading changes while you drive.


Fuel Efficiency Adviser

Score Breakdown

Design 5Features 8Performance 5