# PVC value

**URL:** <https://community.cartalk.com/t/pvc-value/42563>\
**Category:** Maintenance/Repairs\
**Tags:** 323, mazda\
**Created:** [January 14, 2010, 10:56pm UTC](https://community.cartalk.com/t/pvc-value/42563 "2010-01-14T22:56:56Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![simplifying](https://avatars.discourse-cdn.com/v4/letter/s/dc4da7/32.png) [@simplifying](https://community.cartalk.com/u/simplifying)\
**Post date:** [January 14, 2010, 10:56pm UTC](https://community.cartalk.com/t/pvc-value/42563/1 "2010-01-14T22:56:56Z")

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1996 Mazda Protege 323, 116000 miles, normal town driving, I am on my 2nd PVC valve in 1 year and have replaced this thing 3 times since 2004.  
  
  
  
 Why does it needed replacing so often? Is it the way I drive?  
  
  
  
 Thanks!

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**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\
**Post date:** [January 14, 2010, 11:08pm UTC](https://community.cartalk.com/t/pvc-value/42563/2 "2010-01-14T23:08:39Z")

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What makes you think you must replace it?? Three times since 2004? That’s not “often”…

It’s “PCV Valve”

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**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\
**Post date:** [January 14, 2010, 11:13pm UTC](https://community.cartalk.com/t/pvc-value/42563/3 "2010-01-14T23:13:00Z")

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It’s clooging up because you have fumes containing burned oil and probably lots of combustion byproducts being forced up to it from a pressurized crankcase. In short, I suspect your engine is tired. A compression check of the cylinders should be revealing.

By the way, a PCV valve is just a metal “check valve” center loose in a corrresonding container. They can be cleaned by spraying them with any solvent, like a carburator cleaner, until the necter rattles free again.

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**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\
**Post date:** [January 14, 2010, 11:14pm UTC](https://community.cartalk.com/t/pvc-value/42563/4 "2010-01-14T23:14:28Z")

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If they ever start making these out of PVC you and I will end up all confused…

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**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\
**Post date:** [January 14, 2010, 11:22pm UTC](https://community.cartalk.com/t/pvc-value/42563/5 "2010-01-14T23:22:24Z")

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You should clean the entire system, not just the valve. The vacuum port the valve connects to gets plugged up too…

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**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\
**Post date:** [January 14, 2010, 11:26pm UTC](https://community.cartalk.com/t/pvc-value/42563/6 "2010-01-14T23:26:35Z")

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Good point.

Which brings up the question “does it rattle when it’s removed”?

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**Author:** ![cigroller](https://avatars.discourse-cdn.com/v4/letter/c/c68b51/32.png) [@cigroller](https://community.cartalk.com/u/cigroller)\
**Post date:** [January 15, 2010, 3:57am UTC](https://community.cartalk.com/t/pvc-value/42563/7 "2010-01-15T03:57:07Z")

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I’m pretty sure that my old 95 Caravan has a PVC PCVV - I suppose it could be another kind of plastic - but its white, and plastic (except for the guts which are metal). Its not OEM, but I don’t know what the OEM was made of.

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [January 15, 2010, 4:44am UTC](https://community.cartalk.com/t/pvc-value/42563/8 "2010-01-15T04:44:10Z")

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THAT’S my question, too. Why does the PCV (Positive Crankcase Ventilation) Valve, need replacing? Are the oil control rings worn, allowing oil to be burned in the cylinders, and blowing back past the piston rings into the engine crankcase, and, then, being drawn through the vacuum tube to the PCV valve, and on into the engine intake?
