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Old 08-20-2009, 10:30 AM   #7 (permalink)
gone-ot
...beats walking...
 
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...I work with digital "instrumentation" and am aware there are three obvious areas where problems can arise: (1) sample-rate, or how fast the data are gathered by the cars' mpu, (2) output-rate, how fast the resultant data from the car's mpu are placed onto the CAN-bus, and (3) read-rate, or how fast the ecometer attempts to "read" the data from the CAN-bus...however, the CAN-bus itself is synchronous.

...and, since the "delta" in MPH readings seem to be a 'constant' 0.6-mph value, it could also be a problem with "how" the ecometer 'chip' translates the data that it's gotten from the CAN-bus.
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