I have my Crossfire for 2 months and love, I have the code 0730 Transmission Control System It shift fine no problums driving I have a $100.00 deduct how serious is this, also I have a Auto Meter to read gas mileage used it my Chevy HHR for several years but will not work in my Crossfire the dealer says with all of the electronics in the Crossfire it wont work.???