I am having issues with my intake camshaft positioning sensor which i assume is camshaft sensor A. A few months back my check engine light came on and it was the camshaft sensor. i had it replaced with an aftermarket sensor. 3 weeks after i replaced the sensor the check engine light appeared again and it was the sensor. after reading about aftermarket sensors i order the OEM sensor and replaced the sensor not too long ago. once i replaced the sensor the check engine light disappeared. now once again 3 weeks after i replaced the sensor i have the same code appearing on the check engine light. anyone have any ideas what can be causing this? it appears to get worse over time as i drive the car as well...meaning i start to stall out more the more i drive the car with the light on. in addition i also have a O2 heater sensor code showing up which comes and goes for the past 6 years i have had the car. thank you.