     |
Drilling for Oil
by Jim Park
That little black box on the side of your engine really can be your friend. When Engine Control Modules (ECMs) were first introduced in the latter half of the 1980s, drivers concocted some pretty creative ways of short-circuiting the things. Jamming a screwdriver through the cover of the box proved to be one of the least effective ways of regaining control over the engine, but it was on the menu of 'solutions'.
So what's in the ECM for the owner-operator? Like the fleets who use ECM data to monitor their drivers' activity, you can use the data to see where your fuel is going: either to good, efficient use, or up the pipe in idle time, excessive speed, or other poor driving habits. The day-to-day grind can make tracking this information manually pretty unappealing, but opening up a spreadsheet at month's end and tracking the changes from the previous month can make it a whole lot easier. The benefit of this process lies in being confronted by the cold, hard facts, and then tailoring a solution to your problem based on the data you've downloaded. For owner-operators, getting this information from the ECM hasn't always been easy, but it's improving. The easiest method for most owner-operators would be to have it downloaded and a report printed for you by a dealer. We asked representatives from the five engine makers about the cost and availability of the service and answers ranged from $75.00 to $200.00 per download, depending on your relationship with the dealer. That's a crying shame, of course, because the download process isn't difficult or particularly time-consuming. The data can be stored on a diskette or loaded onto your computer, into a spreadsheet or database file, or printed out for your reading pleasure. You can also tap into the ECM on your own, thanks to the modestly priced Palm-type computers and the appropriate connection hardware. Or you can link directly to a laptop or PC just as easily. Products like Cat's Pocket Technician are becoming popular with owner-operators because of the modest cost and the combined ability to download data and make minor adjustments to the engine's operating parameters. Cummins QuickCheck II and Detroit's Pocket Diagnostic Link use the Palm platform as well, along with all the adapting hardware and reporting software built in. Once you've extracted the data, it's permanently stored on your computer hard drive, and the ECM's 'trip' record is cleaned out and reset to zero. The cumulative data remains on the ECM. The other alternative for owner-operators is the dash-mounted displays offered by all the OEMs and engine makers. This data is readily available, though not as comprehensive as what can be had from a full ECM download and reporting exercise. Frankly, while most of the data you might extract from your ECM is beyond the needs of most owner-operators, the dash-displayed data alone is too sparse to be of great value in an analytical or comparative sense.
"Owner-operators can get a real good sense of fuel economy from products like our RoadRelay," says Jeff Van Poucke of Cummins, speaking of that company's dash display. "If they're pulling a hill or running fast uphill, they'll see the drop in fuel economy." The dash displays are useful for real-time fuel economy numbers, and some trip recapping, but nothing is written down. There's no permanent record. If you're right into tracking and monitoring performance and doing all you can to minimize fuel costs, the modest investment in hardware and software is worth it. If you're simply keen on improving the way you use fuel, the dash displays can certainly help. But for comparative purposes, data should be downloaded monthly, or during a regular service interval. Details, DetailsDepending on the brand of engine, the data might be displayed in several different ways, such as tables, bar graphs, or columns of numbers. All the engine makers have some way of revealing what you did during a given period, measured in gallons, hours, miles or percentages of total time, either by all-time totals, trip totals, or trends. All ECMs are set up to capture data in two ways: cumulative, meaning totals from the time the engine was first placed into service; or trip totals, accumulated from the time of the last download. "Both are useful in their own way, and the two reports can be combined into a trend report, which shows averages compared to totals, or totals over several different periods," says Don Coldwell, manager of product reliability for Volvo Trucks Canada. "It all depends on what you want to know." If you really want a scary number, check out the idle-time reports. Most owner-ops would never believe how much total idling time an engine accumulates, but these reports illustrate just how much of your money goes up in smoke. Idle time, by the way, is defined as the base rpm at which the engine rotates (typically around 600-700) without any pedal or cruise/PTO switch interaction. So unless you're using a power takeoff to run some other piece of machinery, your PTO time is pure cost. Driving HabitsWhile none of us likes to be reminded what we've done wrong, the ECM can provide some insight into why your fuel mileage may not be as good as your buddy's. You can track average shift rpm points to reveal poor shifting habits like taking the revs too high before shifting, or use the percentage of time in a given gear to reveal that you've been running too long too far down the ratio ladder. Most ECMs will also record hard braking incidents, where each deceleration above a certain threshold is noted. This might reveal that you tend to drive too close to the vehicle in front of you in heavy traffic, which could demand more frequent 'panic stops'. Some ECMs can track and average throttle position which might show an abnormally high time at full throttle, indicating that you're driving too aggressively in traffic, flooring the pedal to keep up, then nailing the brakes to stay out of trouble. This is expensive territory that might go unnoticed if the bad habits were never pointed out. Load factor might be another indicator of poor driving habits. Load factor, according to Steve Rutherford, truck engine region manager for Canada at Caterpillar, is the amount of fuel being burned, registered as a percentage of the maximum amount that the engine allows. The number recorded is the average of this percentage over a given time period. A 50% load factor indicates that on average, this engine was working at 50% of full load/fuel. A high load factor would result from aggressive throttling in a pedal-to-the-metal fashion. Even your willingness to use cruise control can be shown through the percentage of time in cruise. Cruise control is an arguably more accurate method of vehicle speed control than most drivers' right foot is, so use it. Compare a month on cruise and a month off, and you'll see the difference. Until very recently, access to this kind of information was limited to those with the expensive readers and software packages. But with today's more portable hand-held computers and the right software, even owner-operators can begin examining their on-road performance with a proverbial magnifying glass. Give it a try. What you find might amaze you.
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Our attitudes have evolved, and so have the ECMs. They gather and store a tremendous amount of data today and that information can help immeasurably in improving driving habits and fuel economy. And drilling into that data bank is easier than ever.
