Hyundai Repair: no power, camshaft position sensor, camshaft sensor

Question
My 2006 sonata looses power pulling up a hill. Autozone checked it and code 11 comes up. I replaced the camshaft sensor. The check engine light went off and will come back on at times and it starts missing.

Thank You

Answer
P0011 indicates not a fault with the camshaft position sensor but rather a problem that the camshaft timing on the rear bank is too far advanced.  The fact that this code sets already suggests that the camshaft position sensor is working properly, since it otherwise wouldn't be able to detect the camshaft position.

The most frequent problem causing this issue is that the control valve regulating the variable valve timing on that bank is stuck, often due to metal debris getting caught in the valve.  In this case, replacing the control valve will typically resolve the issue.

I've also seen this issue occur due to infrequent oil changes.  The variable valve timing mechanism is operated via the control valve applying and releasing oil pressure to the actuator on the camshaft sprocket.  If there is enough sludge to plug the small oil passages to the valve and actuator, this type of condition can occur.

Lastly, this problem could be caused by the camshaft timing being incorrect.  This is very unlikely and would typically only occur if there were a problem with the timing chain tensioners or if the engine were disassembled and reassembled incorrectly.