The code P0452 is for "Fuel Tank Pressure Switch - Low Voltage". There is a 13 step process that you need to go through to diagnose this problem which you can find in a service manual for this vehicle.
I would recommend that you find an ASE certified shop with someone who is qualified to repair this type of problem. You can search this site for someone near you.
It's very possible that you have a bad wire, or connection since this is a voltage problem in this circuit.
If you've cleared the code and it comes back, then something else is wrong in this circuit.
〉 Answered on Jul 22nd, 2007 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines