Hello and welcome to Just answer.com, Super mechanic here. About your vehicle.
DTC P0335 Crankshaft Position Sensor Circuit Malfunction DESCRIPTION The Crankshaft Position (CKP) sensor consists of a magnet and coil located next to the flywheel. The voltage signal from the CKP sensor allows the Engine Control Module (ECM) to determine the engine of the RPM and Crankshaft Position.
The P0446 is an evap canister close valve malfunction, (not going to make the engine shut off) but could be a bad valve. I will give you a link for the test for it. However, you will want to replace the crankshaft position sensor first.
Canister Purge Control Valve
LINK TO Purge valve test,
http://www.mediafire.com/?yjzjya2jfkg
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Auto Mechanic
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