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PCV issues


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So I had a Fram PCV valve in before. Oil was getting into the intake somehow and causing the car to run rather crappy :dead:

 

Today I just put in an OEM PCV valve, and the car runs better... but now it idles lower than usual.. why would that be?

 

What causes oil to get into the intake anyways? (It's definately oil, not ATF)

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For the idle, you should remove and clean the Idle Air Control valve (IAC). It's on the front of the throttle body with a 5/8" hose coming off one end, and a two pin round electrical connector.

 

The leaking PCV was supplying not only oil, but also creating a vacuum leak that increased your idle speed.

 

GD

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For the idle, you should remove and clean the Idle Air Control valve (IAC). It's on the front of the throttle body with a 5/8" hose coming off one end, and a two pin round electrical connector.

 

The leaking PCV was supplying not only oil, but also creating a vacuum leak that increased your idle speed.

 

GD

 

I am pretty sure he has done all the normal stuff.

 

 

I am also beginning to have some PCV questions.. I have never managed to actually remove mine before yesterday, because I never concentrated any effort and was always foiled with a single wrench (it was TIGHT)

 

I was investigating because my dipstick is always popped up, like there is positive pressure pushing it out of the tube. I also seem to be experiencing a great deal of oil leaking at the oil cap. I tightened the tabs on the cap, so its a much snugger fit than before, but it shouldnt have been so dirty in that area; the tabs were NOT very loose in any sense, they just had a bit of room for improvement from "reasonable" to "effing TIGHT."

 

My PCV valve seems to function fine. Non-retrofitted hose setup for me, too, and I have never seen one in the JY. I keep my eyes peeled.. but am *I* wrong in thinking that a PCV valve that functions perfectly when its in my hand (i blow, and it seals off good) should not need replacement?

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The early SPFI's had a recall issued some time in 90 or 91 I think for the PCV system sucking oil on long right hand turns. You should apply the recall kit (not real expensive) to keep it from using oil like that. Also clean all the lines out - there's probably a lot of carbon in them.

 

GD

 

Thats a coincidence, I was leafing through my FSM tonight (as you do) in search of a map of all the tubes running around the engine and the PCV system on the 84 EA81's have a Tee joint in the sucking PCV vent pipe that joins it up to the air cleaner thus preventing this oil suck up.

 

So it appears the boffins in white coats had this one sewn up a while ago......

 

Interesting.

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I am pretty sure he has done all the normal stuff.

 

 

I am also beginning to have some PCV questions.. I have never managed to actually remove mine before yesterday, because I never concentrated any effort and was always foiled with a single wrench (it was TIGHT)

 

I was investigating because my dipstick is always popped up, like there is positive pressure pushing it out of the tube. I also seem to be experiencing a great deal of oil leaking at the oil cap. I tightened the tabs on the cap, so its a much snugger fit than before, but it shouldnt have been so dirty in that area; the tabs were NOT very loose in any sense, they just had a bit of room for improvement from "reasonable" to "effing TIGHT."

My 87 had the same problems. The dipstick was popped up after running for any length of time and so on and so fourth, and I checked for excessive blowby and there was none. What I figure was happening is the PCV was blocked. The vavle itself was in there pretty tight but that was easy enough to get out. It worked just like it should and when i reinstalled it I tightened it down as far as it'd go and then backed it off. I think what happens is the valve actually digs into the other side of the block and the positive crank pressure has to go somewhere so it goes through the dipstick tube. After backing it off I never had a problem with the dipstick. coming out.

 

In short, don't overtighten your PCV valves! Doing so will actually block the PCV system and then things just don't work right.

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My 87 had the same problems. The dipstick was popped up after running for any length of time and so on and so fourth, and I checked for excessive blowby and there was none. What I figure was happening is the PCV was blocked. The vavle itself was in there pretty tight but that was easy enough to get out. It worked just like it should and when i reinstalled it I tightened it down as far as it'd go and then backed it off. I think what happens is the valve actually digs into the other side of the block and the positive crank pressure has to go somewhere so it goes through the dipstick tube. After backing it off I never had a problem with the dipstick. coming out.

 

In short, don't overtighten your PCV valves! Doing so will actually block the PCV system and then things just don't work right.

 

Really? :confused: Don't take this the wrong way, but that seems to me, to be alot to take on faith. We shall see; if my dipstick stops getting blown up now that I've removed and re fitted my PCV then I will gladly eat my words.. but in the meantime, does this sound plausible to anyone else? I didn't look too closely, myself. Hopefully you're right; I didn't check my oil today or yesterday, but I will do so tomorrow. Thanks for the input, I certainly never would have anticipated that simply doing what I already did may have "fixed" the problem.

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