Help me find a relief valve.

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Im looking for a pressure relief valve. I want it to open at 5psi. Im going to be putting this on a oil cap on the equinox. The equinox 2.4 has a know pcv freezing during the winter and can blow out the main oil seal. I dont want to spend much more than $10 on the valve. I can only find adjustable ones and everyone says they loose there adjust with age and arnt to reliable. Would like one that has just a spring thats rated for 5psi. Also it cant be to big “for the oil cap” and would need some kind of thread on it for a nut. I made my own custom oil cap for about $20. It just had a valve cover breather on it. Car didnt like it and upped idle fuel trims. So it needs to be a closed system, which i thought i could try some kind of pressure relief valve. What do u guys think?
 
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It should be under negative pressure so just a check valve should suffice to let air out but not in. Just having a breather on it probably allowed the PCV valve to let too much air into the intake and therefore the car injected more fuel.
 
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Doesn't the air tube that goes from the pass side of the valve cover to the air cleaner already do this? That's the fresh air intake for the PCV suction side system? There shouldn't ever be positive pressure because of this fresh air tube.
 

Dylan1303

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Originally Posted By: Fsharp
It should be under negative pressure so just a check valve should suffice to let air out but not in. Just having a breather on it probably allowed the PCV valve to let too much air into the intake and therefore the car injected more fuel.
it doesnt have a pcv valve just a little hole.
 

Dylan1303

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Originally Posted By: oldhp
Doesn't the air tube that goes from the pass side of the valve cover to the air cleaner already do this? That's the fresh air intake for the PCV suction side system? There shouldn't ever be positive pressure because of this fresh air tube.
the hole that acts as the pcv is built in the intake manifold. It can get frozen with condensation not letting the crank case gas leave.
 
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Originally Posted By: oldhp
Doesn't the air tube that goes from the pass side of the valve cover to the air cleaner already do this? That's the fresh air intake for the PCV suction side system? There shouldn't ever be positive pressure because of this fresh air tube.
Yes. What's going on with the fresh air intake side of the PCV system? Is it somehow nonexistent, or blocked? Normally, if there's too much blowby for the PCV valve or orifice to handle, the excess backs up through the intake, to minimize positive pressure in the crankcase. Also why don't other cars with this crude form of PCV system have the same freezing issue?
 
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Dylan1303

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Originally Posted By: CR94
Originally Posted By: oldhp
Doesn't the air tube that goes from the pass side of the valve cover to the air cleaner already do this? That's the fresh air intake for the PCV suction side system? There shouldn't ever be positive pressure because of this fresh air tube.
Yes. What's going on with the fresh air intake side of the PCV system? Is it somehow nonexistent, or blocked? Normally, if there's too much blowby for the PCV valve or orifice to handle, the excess backs up through the intake, to minimize positive pressure in the crankcase. Also why don't other cars with this crude form of PCV system have the same freezing issue?
Poor design by chevy idk. If u look up frozen pcv equinox theres tons of cases of it.
 
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Originally Posted By: Dylan1303
Originally Posted By: oldhp
Doesn't the air tube that goes from the pass side of the valve cover to the air cleaner already do this? That's the fresh air intake for the PCV suction side system? There shouldn't ever be positive pressure because of this fresh air tube.
the hole that acts as the pcv is built in the intake manifold. It can get frozen with condensation not letting the crank case gas leave.
The PCV maybe but I would not think the fresh air hose pipe nipple would freeze up, it's at least 5/16" I.D. cheers
 
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