We just had a problem like this on my father's 2007 Dodge Caliber.
The Caliber's sending unit is also the fuel pump and filter and the whole assembly goes into the top of the fuel tank.
We were getting false readings after my father's mechanic had installed the new unit. We took it back and they turned the unit a little and it's been fine.
When they installed the new one it was hitting something in the tank, so the float wasn't moving correctly.
I don't know if the Crossfire has the same setup, but maybe the float is hitting something?