Code P0341

Car starts just fine but has a rattle noise whenever accelerate and code pop up P0341 Saturn - Camshaft Position Sensor 'A' Circuit Range/Performance -- Possible causes: - Faulty Camshaft Position Sensor - Camshaft Position Sensor harness is open or shorted - Camshaft Position Sensor circuit poor electrical connection - Faulty starter motor - Starting system circuit - Dead (weak) battery I've changed the sensor but still same issue I've tested the connector its getting power and ground and a 5 volt signal. what else should i check? the check engine light always on before start the car but goes off after car is running. but whenever i check for codes with scanner it's no code stored, but p0341 pops up under pending codes. whenever i clear code and turn car off the check engine pops right back on even though there's no code stored in ECU.