I just went out and checked my 1990 5.7L 350 for shorts in the wiring since a mechanic told me at night is the best time to do so. I noticed my pcv valve sounded like a bug zapper buzzing. I am pretty sure this is not normal but I just replaced my pcv valve back in October. I have been doing a lot of diagnostic work on my vacuum lines and egr. Does the buzzing mean it needs replacing already???