My dash speedometer shows a little bit of needle wobble. No problem.
But VmsPC shows the correct speed most of the time. Slight +|- 1 mph fluctuations. And then an occasional + 5 mph spike. Or a series of spikes. When I glance at the display my first thought is I'm going too fast.
Is there some damping parameter I can change so it acts more like the dashboard speedo?
Just shooting into the dark here. Could it be the speed sensor itself? A bit dirty or bad connection? On our coach, The VmsPC and the OEM speedo is dead accurate to the GPS and I haven't seen any spikes at all.
Sounds like a speed sensor/ dirty connector. Like Bigdog mine is dead on both speedo and VMSPEC.
VMSpc reports speed based on what the engine computer reports. It does not use any mechanical speedometer connections. Speed is based on data originally provided to the engine computer, tire and wheel size, drive ratio, gear you are in and rpm. Tire revolutions convert to distance over time gets you MPH. The same calculations get you distance. The engine computer reports this over the data bus. VMSpc grabs the data as it comes over the bus and reports it. Silverleaf tells me there is only a small amount of smoothing or averaging going on. They tell me that the next release (due out almost a year ago) will have more aggressive ability to discard data that is significantly out of range and do some additional stability management. How is that for promotional speak?
So for now it is up to you to ignore the outliers. Don't worry too much about it. For some engines the 3.x versions work a bit better. For most the 4.0.8 version will be fine until version 5 comes out.
My dash speedo reads just under VMSpc. Odometer reads about 1% low compared the the computer. I am going with the engine computer.
You can put in corrections (relative and absolute) for these reading under engine corrections. The correction is the hard part to figure.
Gee Roger, You should go on TV and help sell flex tape. :))
Mine does the exact same thing while driving.. Now sitting is another story... it does nothing :)) ^.^d
I was hoping the smoothing parameter was user defined. Oh well.
Thanks
Under the Advanced Menus/Engine Corrections make sure you check the Request Fuelmeter and Odometer boxes. I guess this prompt the computer to send this data more often.
Thanks. It's worth a try. More frequent samples would likely help. Less delta v between samples.