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pcv valve sounds like a bug zapper!

Discussion in 'GM Powertrain' started by silleffej, Dec 22, 2010.

  1. silleffej

    silleffej New Member

    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???
  2. stephan

    stephan New Member 1000 Posts

    Usually they start buzzing when they are worn out & there is too much clearance btw the ball & the housing, but since you just replaced it in October I'm thinking maybe it's just an inferior brand (China/Taiwan/Mexico) & not made to proper tolerance.
  3. silleffej

    silleffej New Member

    btw ball and housing,

    are you talking about the rubber grommet the pcv plugs into?
  4. stephan

    stephan New Member 1000 Posts

    NO, not the rubber grommet. The ball is inside the PCV housing. That is what is rattleing back & forth & buzzing.
    Where did you buy it? Pop it out & see if you can read the vendor on it somewhere.
  5. silleffej

    silleffej New Member

    it was bought at local auto parts store, I think it is china made. It was rather cheap. would a higher end pcv really perform better?

    ---------- Post added at 10:21 PM ---------- Previous post was at 10:18 PM ----------

    I don't even know if there is a such thing as a higher end pcv valve. I have never seen one cost more then a couple of dollars.
  6. stephan

    stephan New Member 1000 Posts

    Yes there is a difference btw a good one & a bad one. Yours is a bad one. I've had mine in my truck for 35,000 miles & it's still good. I know you haven't put many miles on your burb since October, so the pcv you got is just a cheap one.
  7. silleffej

    silleffej New Member

    I took the pcv valve out and shook it. I can still hear a rattle, doesn't that mean it is still good? I will probably replace it anyway but just checking.
  8. stephan

    stephan New Member 1000 Posts

    Yes & no. They should rattle when you shake them up & down. This tells you that it is not stuck with crud inside & doesn't need cleaning. That is a test on an old one to see if it is still free, & NOT STUCK, but this is not the problem with yours. Yours is TOO FREE.. You just need a better quality one.

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