PCV valve...

[1991acclude]

here is something funny, today my dad came by and we were comparing cb7 auto to manual both 91's and he pulled his PCV valve out of the valve cover and his car sputtered, I pulled mine and nothing happened. Is there something wrong with my intake manifold or his.

[accordaffair]

I think his, the engine vacuum should hold the valve closed....troubleshooting actually stipulates squeezing the tube and listening for a clicking noise

[F22HB]

Possible bad valve. It should be closed under vaccum.

[stelvio]

haha...you showed him up lol

[evil_demon_01]

I think his, the engine vacuum should hold the valve closed....troubleshooting actually stipulates squeezing the tube and listening for a clicking noise

X2 sound like his is bad.
To check this you could swap yours onto his, or simply clamp the hose on his with a pair of pliers to confirm the idle comes normal again, each time you clamp it, it should click, if not then its faulty, and I would suspect either the spring is broken or the ball has come out.
If you take it out, you should only be able to blow through it 1 way, If you can blow both ways it needs replacing.
If its faulty, is the same as having a vacuum leak which will cause a bad/rough idle

[1991acclude]

so...

his is bad not mine, upon removing my PCV valve my car doesn't stall or have a rough idle, I can hear suction from the valve cover thats all. As for his upon removal, it idles rough until he covers it with his finger or plugs it back in. I was thinking of seafoaming our intake manifolds today. Ill check to see if air can go through the valve one way.

[ancona46]

just change them both they are cheap as dirt

[soon2bdropped]

i thought it should be open during vaccum because that valve needs to open to allow blowby and crankcase ventialation back into intake manifold to get reburned?

[soon2bdropped]

Bump..

[evil_demon_01]

Yes it is open, a very slight amount, if it was just straight open (and flowed alot of air) you would have idle problems due to a vaccum leak.
Take the pcv right off and see how your car idles. Then plug it and put a small hole in the plug - about 0.5-1.0mm and you will see how the small "vacuum leak" doesn't affect the idle

For more detailed info read up here.