Volvo: check engine light, evaporative emissions, emission system

Question
My check engine light keeps coming on. I took it to Midas and they said it could be the Evaporative Emissions System Sensor- but contrary to that, the temp gage keeps dropping down like the car is freezing, but it is running perfectly fine. Do you think it's the coolant temp gage? I don't know what it could be. Also the blinking arrow for the transmission comes on, but only after going over 60mph. It comes on and goes off, could that be apart of the check engine light? I've had the transmission looked at and no codes come up for it, do you think there could be a problem with that?

Answer
Rachel,
I am not sure of the year and model of your car, but some have codes due to the emission system. If the arrow is flashing that indicates there is a fault code in the trans control unit. If the temp is not coming up and the heater is not real hot you may have a bad t/stat in the engine, and that will also in some models turn on the Check Engine light. On some vehicles the Volvo scan tool can test the gauges to see how well they work.