Contour Enthusiasts Group Archives Forums Modifications Duratec Performance How is the load percentage calculated?

I just got an OBD-2 scanner (www.obd-2.com). I got a CEL, so I could finally justify the money to buy it. The software is great for those who are wondering. It turned out my ProFlow MAF was causing a rich condition, so it will need to be recalibrated . Anyway, one of the parameters the software can monitor is the load percentage. Does anyone have any idea how the load percentage is calculated? (i.e. what does it mean?)

Load is just some math that the ECU does to know how much fuel and spark to add at any throttle position. Taking the MAF voltage, by vss signal, by TPS will get you a value. It's up the the software engineer what he wants the value to be and comes up with a table to track those values and interpolate between the values for middle ground values...

20MPH cruise on flat ground takes less fuel and spark then 20MPH going up a hill. How does the ECU know? More TPS voltage will change the value on the load tables...

As an example, 20MPH = TPS value 1, MAF value 1, vss of 5. 1 X 1 X 5 = 5. The ECU would then use the fuel spark maps for value 5.

20MPH up a hill = TPS value of 2, MAF value of 2, vss of 5. 2 X 2 X 5 = 20. The ECU would use the fuel and spark maps for the 20 value.

Over simplification, I know...

Thanks Brad. I figured it was something along those lines, but I thought someone might know specifically how they calculated it. I just wanted to satisfy my curiosity.

If you can find a binary reader, you can scan the stock settings and find out what the Ford Contour values are. Truth be told, they can make up any values they want to as long as they match the preset table values. For instance, my GM 165 series ECU multiplies MAF voltage by (vss readings divided over RPM) to get their load rating. A Ford Mustang my multiply all three values instead to get their preset table reference number. It's not a Ford-wide format, or even a Contour-wide format for that matter, which is why you must have a *mask* file to read the binary file of an ECU. The mask file is the numbers that you would have to tell the Superchips tech, read off of your ECU. Each Contour would be different...