so if the sensor is bad , will the ecm still adjust thee timing? I have the same issue with a P0335 and a P1336 code. the engine still seems to run properly but I wont be able to get it smoged .does the Tachometer run off of the Crank sensor, my tach still functions. I had the heads off and reconed and changed the sensor when I get to it easily then 350 miles later , it is throwing codes