2006 Chevy Monte Carlo P011 - camshaft sensor code

have changed camshaft sensor, camshaft actuator and still is running a p011 code on my car.... when the problem first started a message came through my dash reading engine not producing full power..... I am having hard shifts in 2nd and 3rd gear... run great on the interstate and at high speeds. at low speeds hards shift and then the check engine light will come on... after a day or two it will come back on.... also pops on after getting off the interstate. what's wrong know nothing else to de..... someone suggested that the magnet somewhere on the camshaft actuator or camshaft may be burned out.