A quick glance told me a lot of information: 65 mph, 23.4 average mpg, 192 degrees water temperature, and 14.2 battery voltage. A punch of the button on the face of the gauge told me I had 208 miles to go at the present rate of fuel consumption, and that so far I had spent $123.62 on fuel. I could even compare a lot of this information, such as fuel use, with my travel the day before.
Another few touches of a button gave me maximum coolant temperature, engine rpm, or even maximum rpm. I could also find out the number of miles I've travelled at what average speed and how much fuel I had used to do so. Not only that, but I could get the fuel use should I want to not only in miles per gallon, but in kilometers per gallon, miles per liter, or liters per kilometers. My speed could show in mph or km per hour. Then there were some really trick things I could get readouts on, like percentage of maximum power being used, throttle position setting, fuel system loop status, timing advance/retard, or intake air temperature. If my service engine light came on, I could read the trouble code and then remove it after the problem was fixed.
Pretty darn cool, right? Was this some new "not yet released" automobile that I was driving? Hardly! I was using a 4.8-inch-wide, 1.5-inch-high, and 1.0-inch-deep gauge that plugged into the diagnostic port of any vehicle that uses the OBD II system. That means that it worked just as good in my '01 Duramax diesel truck as it did in my '96 Grand Cherokee.
I really didn't know such a tool existed until one day fellow journalist Jimmy Nylund and I were having our mostly bull-session weekly phone call. Our conversation centered around "wouldn't it be nice if one had a multitude of digital gauges that would give you some accurate information as to engine performance other than what the factory gauges offered." As an example, the fuel gauge on my Duramax goes from half a tank to "needs fuel, now!" much quicker than it does from full to half.
Wouldn't it be nice to know how your fuel mileage is affected when, say, pulling a grade or bucking a head wind, by either changing gears or backing out of the throttle a bit? Wouldn't it be nice to know what percentage of available power was being used when the cruise control was doing the throttle manipulation? Wouldn't it be nice to know that when the fuel tank gauge read 1/4 full you really knew just how much further you could drive and if you slowed down a bit that you could make it to the next station without sweating it? Does it really make a difference if the tailgate on a pickup is up or down in relationship to fuel mileage?
After I got rid of Jimmy (er, hung up), I did a couple of different Internet searches until I came up with the ScanGauge.
OK, by now, you're saying that I must be using some very expensive tool that I bought off a Mac or Snap-on tool truck. You're wrong. I found a company called Linear-Logic LLC (888/433-5664, www.scangauge.com) that made just such a tool. The gauge is, of all things, called the "ScanGauge II" and the price was about $170. That's about an eighth the cost of a specialized OBD II scanner and does almost the same job, or at least everything that I have any business messing around with.
This tool is pretty fantastic with a lot of other things that it can do, like store most of the high readings, such as water temperature, speed, and engine rpm in its memory bank. There is even some stuff for the real computer geeks called a X Gauge that goes way beyond my needs or knowledge. What I do know is that it is a great tool as well as a play toy.
