Charlzm - sounds like you and I have identical issues. so maybe we can work this together and post what we find out in order to help each other.
see my post
http://www.grandprixforums.net/sound...you-53934.html
Also, my HUD will go out by itself and then come back on...
BTW does your performance shift work at this point?
Appearently the trip calculator does a self test and if it does not get the serial data that it wants within 10 seconds it flashes zeros. Here is a blurb from alldata
"The trip calculator performs an error detection when a serial data stream is not present for 10 seconds. If the trip calculator is not able to calculate a value, due to any missing data, the display shows a flashing 0 when the mode is selected. The trip calculator updates the display with the correct information for each mode that is selected within a given time frame."
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