It's critical that your engine be in time in order to run properly. I'm speaking first here about the mechanical timing of the engine, but you also need to make sure your ignition timing is correct for your engine to perform properly. More than one person has come to me stating that they had replaced just about every part on the engine and they still have a performance problem. Then I ask, "Did you check the mechanical timing of the engine?" I'm often met with, “No, but I will.” After they come back, they report that either the timing had jumped a tooth (if it was a timing belt) or there was some other issue that caused the timing to be off.
Everything about engine operation has its time. If the mechanical timing of the engine is off, everything is off. The ignition timing, the injector timing, all the electrical systems: All of it suffers if the engine is not in time. So if you have a performance issue, check to see if the engine is in time mechanically before you start buying parts, especially if you have a code for a cam or crank sensor. These codes can also be set if the engine timing is off, not just because of a sensor issue. Once again, just because you have a code for something, that doesn't mean you can start replacing parts. Verify those parts are bad first, and in the case of cam and crank sensors, check the mechanical timing of the engine before you start replacing sensors.