Anyone had this problem or know how to fix it? The guys who installed it say its hooked up correctly. Needless to say it throws the nav off. If I stop for more than a few seconds, my route is recalculated.

Help

what kind of car is it?

Its an '06 350Z.

sounds like they hooked it up to the tach maybe??

yeah, sounds like somethings hooked up wrong. the only time i've seen that happen is in a car without a speed sense, and using a speed pulse generator. the generator can pick up noise from a loud exhaust and cause drift at stops. but that shouldnt happen with an actual speed pulse