One Way Check Valve

Detroiit

Active Member
May 27, 2014
305
60
38
Detroit MI.
I installed a one way check valve inline with my pcv valve. Not sure if its necessary or can be detrimental in anyway. The valve only lets the vacuum through and blocks off the positive pressure from going back into the pcv. I have a 90 fox with boosted 306 v3 Si kit.

So my question's are:
Is this check valve hurting anything?
Should I remove it?
Is it a good idea?

I'm not sure if the intake is sucking oil under boost through the PCV system. I did look into the turbo thunderbirds pcv and it seemed like it was exactly the same valve that is in my car. It restricts the flow into the block when blowing in the valve but a good amount still can get through.

Whats your thoughts on what I installed?
 
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*Newb alert* You're trying to prevent "blow by" right? I recently added the same kit as you did and didn't give much thought to the issue until reading your post. I hope your method works. It seems to be the simplest, everything else I've read about involves capping this and that runnin lines here and there and adding catch cans.
 
You do not want boost running back into the crank case from the intake. In a NA car, the PCV valve is the one way check valve. So your valve may be redundant or a good upgrade for the extra pressure in the intake. Either way, it does not sound like a bad idea.
 
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I tried all this stuff and ended up plugging the pcv and running a filter on my VC until I get my fabbed valve covers and catch can in
 
I have my PCV gone i have a breather in my one valve cover going with a catch can system.now but im going to install the PCV and try that so normal driving it will do what its suppossed to then under boost it will vent to the catch can...if it doesnt work i cap the PCV again....
 
Not sure I understand the need for a second one way valve. Are you thinking the PCV valve isn't working or strong enough?
I pulled the pcv out of my car and blew in it and some air did go through it was not sealed like a proper 1 way check valve is.. I also went to auto zone and they got me a turbo coupe pcv and it was not absolutely sealed either some air did go past it. Is a proper PCV valve suppose to act like a 1 way valve? Absolutely no air should make it past it?