A check engine like comes on and then my car begins to hiccup and misfire. Sometimes it is like there is no power and then all of a sudden it goes away. I have check the codes and get the two listed above. Have replaced the crankshaft sensor and the sparkplugs - the problem still remains.

 

Check the Camshaft Sensor, wiring to the camshaft sensor (the wire is in a position where it is susceptible to breakage due to age, heat, and the tight bend put in the wire.) also check to see if your timing belt is loose. Most probable cause is a bad timing belt tensioner / idler pulley.