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PCV valve - how often to replace, how can you tell if bad?

  • Thread starter Thread starter bloopbloob
  • Start date Start date Apr 2, 2008

bloopbloob

Member
Sep 27, 2006
578
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Alberta
Apr 2, 2008
#1
  • Apr 2, 2008
  • #1
like the title, how do you know when your PCV valve is done? i'm trying to find a mysterious oil leak, no luck, but its coming from the pcv area/(back of the engine where i can't see much....) so i pulled it out but didn't even know what to look for... but it looked fine to me.... replaced it last year...
 

jtfairlane

New Member
Mar 5, 2006
468
3
0
Apr 2, 2008
#2
  • Apr 2, 2008
  • #2
Service Manual calls to replace at minimum every 60,000 miles. The wire/mesh filter directly underneath the PCV Valve, which helps minimize the amount of oil that is introduced to the intake manifold, should be replaced every 30,000 miles.

To test the PCV Valve, remove it from the plastic grommet in the lower intake. Shake the PCV valve, if it rattles, it's most likely fine. If it doesn't rattle, the valve is sticking and needs to be replaced.
 

bloopbloob

Member
Sep 27, 2006
578
4
16
Alberta
Apr 3, 2008
#3
  • Apr 3, 2008
  • #3
ok mine well mine rattles and looks clean, and just fine.... so how can the pcv cause an oil leak back there? cuz thats what everyone said to look at for my source..... ? but everything seems ok with it and the hose....?
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
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108
Chicagoland
Apr 3, 2008
#4
  • Apr 3, 2008
  • #4
If it's leaking near the back of the lower intake, it's probably leaking between the block and manifold. If the PCV is sticking, you'll typically end up with oil in your upper plenum before you'll have a leak.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Apr 3, 2008
#5
  • Apr 3, 2008
  • #5
And a bad PCV valve or excessive clogging in the circuit can cause oil leaks elsewhere, though the underlying cause is the blocked PCV pathway (the crankcase vapors start finding a new path of least resistance).

I like to see folks check the plunger resistance in the PCV valve itself. The valve has a spring in it - if the spring broke, the valve would still rattle but the valve would not be considered servicable.
 
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