CNET logo Why You Can Trust CNET

Our expert, award-winning staff selects the products we cover and rigorously researches and tests our top picks. If you buy through our links, we may get a commission. Reviews ethics statement

PLX Kiwi review: PLX Kiwi

PLX Kiwi

Antuan Goodwin Reviews Editor / Cars
Antuan Goodwin gained his automotive knowledge the old fashioned way, by turning wrenches in a driveway and picking up speeding tickets. From drivetrain tech and electrification to car audio installs and cabin tech, if it's on wheels, Antuan is knowledgeable.
Expertise Reviewing cars and car technology since 2008 focusing on electrification, driver assistance and infotainment Credentials
  • North American Car, Truck and SUV of the Year (NACTOY) Awards Juror
Antuan Goodwin
6 min read

Among the many new devices promising to boost fuel economy during these times of high gas prices, the PLX Kiwi tries to improve the driver rather than the car. The PLX Kiwi is a training device that monitors driving habits and assigns the driver a rating based on how "green" it finds the driving style, with 100 being the best. For the most part, the Kiwi does just that, but issues with the way the device interfaces with the vehicle may leave some drivers scratching their heads.

The Good

In addition to helping increase fuel economy by monitoring driving habits, the PLX Kiwi lets drivers check and clear OBDII engine warning codes.

The Bad

The Kiwi depends on the car's sensors to calculate fuel economy and may require calibration to see accurate numbers.

The Bottom Line

While it is a good training tool to help motorists to drive more efficiently, the PLX Kiwi will not miraculously boost your fuel economy.

Drivers interact with the Kiwi through its 2.2-inch OLED screen and a directional pad with a center select button. Made of glossy plastic with a faux chrome bezel, the Kiwi seems to generate an inordinate amount of glare, but the display is bright and easy to read, even in direct sunlight. The buttons require a firm and deliberate press to register, which can make menu navigation cumbersome.

Powered by the vehicle's OBDII port (found in the cabins of all new cars), the Kiwi doesn't require an external power cable. When the vehicle is turned off, the Kiwi goes into a standby mode that continues to draw power. If the vehicle is to be parked for an extended period (say a month or so) the Kiwi can be deactivated with a power switch on its side.

On the bottom of the Kiwi is a micro USB port that is used to upload animations, which we'll discuss later in this review.

The Kiwi boasts nine key features, each represented by a main menu option. The first option brings up your Kiwi score, a 0 to 100 rating of how economically you're driving based on four parameters: smoothness, drag, acceleration, and deceleration.

Your Kiwi score is based on smoothness, drag, acceleration, and deceleration.

The Kiwi also lets you monitor your average and instantaneous fuel economy with the MPG meter. Additionally, by inputting the price per gallon of gas in the Setup menu, the Kiwi will also keep track of how much the current trip is costing and how much money you've saved with your thrifty driving.

A rather neat Drive Green option offers 20 training routines designed to help drivers learn to be more conscious of their driving techniques. One lesson, for example, had us maintaining a high acceleration rating for a timed period, while another had us keeping our deceleration score high through judicious use of the brakes. While the tests are good training tools for making a lead foot into a green one, we'd recommend that they're reserved for especially light traffic, as some of the tests (particularly the braking tests) can be a bit distracting.

Our test vehicle is in good shape, with no error codes reported.

Keeping a vehicle in good running order is an oft overlooked step in maintaining high fuel economy. With this in mind, PLX has included an engine check mode to display trouble codes when the check engine light comes on and a sensor mode for viewing the diagnostic information being output through the OBDII port. This cool feature can help motorists not only save at the pump, but also at the repair shop. However, the Kiwi only displays the code, so the motorist will have to look up the code's meaning in a shop manual.

Other features offered include logging past Kiwi scores and miles per gallon, and a "fun mode" that displays a customizable animation (uploaded through USB) of a flower that blooms as your Kiwi score rises. We didn't find the fun mode to be much fun at all. In fact, we thought it was quite useless, since it mostly just displayed a static picture of a flower at half bloom for us.

Setting up the PLX Kiwi was a simple plug-and-play affair. We first located our test car's OBDII port (in most cases, located under the dash beneath the steering wheel), and connected the Kiwi. After finding a suitable mounting location for the device, we started the car up and were greeted with a warning screen, a green driving tip, and finally the main menu.

Selecting the Kiwi score option, we spent a few hours exploring the streets of San Francisco under the watchful eye of the Kiwi. At first, all was well. The Kiwi kept track of our throttle position, braking pressure, and speed. If we stabbed the throttle, our acceleration meter dropped, lowering our Kiwi score. If we jumped on the brakes, accelerated past 55 mph, or drove erratically, our Kiwi score dropped. However, by accelerating smoothly, keeping our speed in check, and anticipating stops early, we were able to raise our Kiwi score to a respectable 82 points. Upon stopping to check our fuel economy, we expected to see equally respectable miles per gallon, but what the Kiwi displayed was surprising.

The Kiwi was reporting that our test vehicle, a 2007 Chevrolet Aveo, averaged a meager 7 mpg. We knew that we'd get some variance from the EPA estimated 23 mpg city and 33 mpg highway, but we were confused by such low numbers. We attempted to raise the average miles per gallon with a few hours of highway driving, but were only able to get Kiwi to display a combined mpg of 14 mpg. At the pump, we calculated our actual mpg to be approximately 26 mpg.

Alarmed by the discrepancy between the actual mpg and the reported number, we called PLX tech support. After walking us through a simple diagnostic using the Kiwi's sensor menu, it was explained to us that our test vehicle wasn't reporting an airflow parameter that the Kiwi uses to calculate mpg and that the device was essentially making its best guess using the rest of the information available. Tech support then walked us through adjusting the discrepancy using a calibrate mpg option in the setup menu.

With the help of PLX tech support and the sensors menu, we were able to figure out why our test vehicle was showing such low mpg.

Instead of recalibrating the device, we chose to test it in another of our test vehicles, a Mazda CX-9. After connecting the Kiwi and confirming in the sensor menu that everything was in order, we drove the SUV around for a few hours and got a more reasonable 16.5 mpg (EPA rated 15 mpg city and 21 mpg highway).

We can't blame the Kiwi for the issues we had with our first test vehicle, as the Aveo simply didn't have all the sensors the Kiwi needed to accurately report miles per gallon. In the device's defense, the calibration option is as good of a solution as can be expected, but the conclusion we reached was that the Kiwi wasn't always as plug and play as it's advertised to be.

In sum
While we don't like the squishy buttons, the Kiwi has a nice-looking display and is very easy to operate. We like the one plug approach to setup, but, depending on your vehicle, calibration can be a chore. In vehicles with all of the requisite sensors, the Kiwi performs exactly as advertised. However, if your car has a good trip computer, some features of the Kiwi will be redundant.

We could argue that the driving techniques the Kiwi teaches are essentially common knowledge and could be learned for free, without the need for a $299 device. That doesn't mean that the Kiwi is worthless, but the key word when describing the Kiwi is "helps." The device's Achilles' heel is that it depends on the vehicle's sensors to report accurately and the driver's improving skill to be useful. For those of us with right feet made of lead, the Kiwi could pay for itself within the span of a year. However, if you're already a thrifty driver, piloting your vehicle to its maximum efficiency, the Kiwi will be very limited in how much it can improve your fuel economy.

Score Breakdown

Design 6Features 7Performance 6Support 0