Valve behind head on 92 240SX

[Zoom45]

There is a valve mounted behind the head on my S13 92 Nissan 240SX DOHC that is about 4" below the fuel regulator but I don't know what it's called. It is vacuum controled and has a small rod that goes up to something. The car is very clean but the vacuum line going to this valve appears to be oil soaked or wet with fuel. All the other lines around it are clean. Is it possible some gas could be bypassing something and getting into this valve through a vacuum line? The car has been intermittenly quitting. It may run fine 2 weeks the quit. Now I can crank it but it runs rough at idle and has a slight miss at acceleration but the rpms will manage to redline it after it clears out. It sounds like a vacuum leak is in the area of the wet hose. The vacuum line to the valve is short and curves from the valve to a small metal tube on the back of the head. It's located at the bottom of the head and I can't hardly see it with a light. I sure don't know how I can get my hand on it to change it out. Any ideas? The computer only shows a code 55.Thanks,Zoom

[Zoom45]

I think they call that valve a swirl valve. I kept fooling with it today and the miss finally cleared up and I drove it about 2 hours with no problems. It does fine for a couple of weeks the all of a sudden I'll have to tow it home again. These intermittent problems are the worse.Zoom45

[grecco28]

you are right is the the swirl control valve, and it works only as an aux. air bypas in the intake manifold, when you are in idle close one pasage of air (the larger) or the normal driving way for the air intake this allow the air inlet run in the shorter pasage so the engine run more steady in idlethis valve is vacum operated, when you replace the damaged hose checkthe function with engine running in idle tap a litle the throatle with you hand in engine bay and look if a litle rod comes up when tap the gas.if not maybe the diafragm is damaged or the swirl throatles (4 inside the manifold) are jammed..

[danielsan]

you are right is the the swirl control valve, and it works only as an aux. air bypas in the intake manifold, when you are in idle close one pasage of air (the larger) or the normal driving way for the air intake this allow the air inlet run in the shorter pasage so the engine run more steady in idlethis valve is vacum operated, when you replace the damaged hose checkthe function with engine running in idle tap a litle the throatle with you hand in engine bay and look if a litle rod comes up when tap the gas.if not maybe the diafragm is damaged or the swirl throatles (4 inside the manifold) are jammed..

what did you just say?? hurt my head trying to read that.