Anyone ever had this problem before?

This happens once in a while for me when I am trying to log my kart's run data with the G2x. The gps map just... jumps all over the place and a lot of times my trackmap never matches with my runs...

its strange that I never have any problem with IQ3 on a sedan race car, but can never get it to work on the go kart... cant seem to figure out how they would be different.