Yes, P0453 is the fuel tank pressure sensor, but it's specifically for high input. Since the gas cap is supposed to seal airtight, a leak should cause low input. More likely something blocked in the EVAP system, or a bad pressure sensor.

If you're comfortable with troubleshooting the EVAP system under the car, there's a very detailed procedure in the Helm repair manual. But it seems like a disconnected hose would cause a low pressure reading, not high.

 

Usually high and low input refer to voltage ECU senses. Depending on the sensor, high pressure could be low or high voltage signal output (input to ECU) and same for sensor low pressure signal. Makes your head swim.

good luck

 

well the light came on when I got my sounds installed....do you think that has anything to do with it? Now, once in a while, when I turn the car off and get out, I close the door and the bower goes completly dead. I know this because when I try to turn the alarm on nothing happens. I have to go back in the car put the key in the ignition and then the power comes back.