# 1992 Nissan Stanza "Mystery Valve"



## voodoo917 (Jun 21, 2013)

Can anyone tell me what the name of this valve is and what it does? This picture is not from my 1992 Nissan Stanza, but it is just like the valve that fell out of mine. 

It's been running really raggedy and I was looking around for reasons why, when I noticed it missing. It changes the idle speed when you plug the side of the hose coming from the engine. 

I showed several auto parts store employees the actual car and this picture and none of them could tell me what it was, what it does, or how to get another one! Please HELP!


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## smj999smj (Jan 1, 2006)

It's a one-way valve between the intake manifold and the vacuum tank. To test it, you should be able to blow through it in one direction, but not be able to blow through it in the opposite direction. It's likely a dealer part...if they can find it!


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## voodoo917 (Jun 21, 2013)

Thanks smj999smj! Do you happen to know the technical name for this "one-way valve"? Everyone had already come to that conclusion, but no one seems to know if it "regulates" air flow, or if it is an "unrestricted" one-way valve. I just need to know the technical term for it so that I can find one of them.


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## wilburk (Dec 29, 2012)

It's likely just called a vacuum valve. I would definitely check the dealership. 

This may help, as well:
Part Detail


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## jdg (Aug 27, 2009)

If that one-way valve is actally going between the intake and the vacuum tank, then it should be an unrestricted type. The vacuum tank is there for a sort of "vacuum reservoir" for either power brakes, maybe the doors for the defroster/vents/etc. My guess would be any old check valve for any vacuum system will work just fine as long as it fits the vacuum lines themselves.


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## smj999smj (Jan 1, 2006)

It's technical name is a "vacuum valve assembly," and it's Nissan P/N: 14958-V6700. It's just a regular one-way check valve, similar in function to a brake booster check valve. It's been a while, but I think the other line off of the vacuum tank goes back to the idle speed valve. It doesn't operate mode doors or anything to do with the HVAC system; those doors are all cable controlled, if I'm not mistaken.


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## voodoo917 (Jun 21, 2013)

Thanks for the info! I went ahead and bought just a regular check-valve from the auto parts store. I'll try it out today sometime and see if that levels the motor back out, if not I guess I will have to order it from the dealership. Thanks for the part number smj999smj, that is a tremendous help and exactly what I needed to know!


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## smj999smj (Jan 1, 2006)

If the aftermarket part doesn't fix your problem, the Nissan part probably won't do anything either. All you need to do is blow through it from each end to test it.


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## voodoo917 (Jun 21, 2013)

Thanks for everyones help! I just used the universal one way check-valve and it worked fine. Smoothed out the shifting and took some of the vibration out of the engine.

Thanks again!


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## newave (Sep 4, 2015)

can any one post a vacuum hose diagram for the ka24 e 90-92 stanza engine


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