PVC coming out

[a94cobra]

94 Cobra, supercharged, the PVC keeps poping out.

First of all what denotes a bad PVC? It rattles when you shake it. So I assume it's good.

I had a breather on the VC. But I really didn't like it. I replaced it with the cap. Now the PVC is blowing out. So I am pressurizing the crankcase. But how? I thought I had the vacuum routed so this wasn't an issue. Maybe I missed something.

Anyone had this issue?

 

[LS1PUSSOUT]

Its just something your supposed to change out every so often even if its not bad. Just go get a new one. Theyre $7 from the dealer.

 

[a94cobra]

Do you think that is the problem?

 

[tt460]

A PCV valve popping out is a sign that your crank case is being pressurized under boost. There are two potential causes for this:

1) You have a cheap PCV valve that doesn't have a check valve incorporated into it. If you blow on the hose connected to the PCV valve, does it go through the PCV valve? If so, your blower is doing the same thing and pressurizing your crank case under boost. You can either put a check valve between your PCV and intake manifold or buy a PCV valve from something that was boosted from the factory (like an 03-04 Cobra).

In most cases, the PCV valves that you would buy at the parts store are inadequate at preventing boost from going into the crank case. I had a twin turbo with this problem and I installed a PCV valve from an '88 TurboCoupe and that fixed it.

2) Piston ring blow-by. Just hope your problem is the first one. The fix for this is a rebuild.

 

[a94cobra]

The second one is what I am afraid of. Not that I can't rebuild. I just don't want too.

Should there be other signs, like smoking out the tails pipes, or anything like that?


I have the PVC and VC re-routed to the the intake before the S/C. This runs thru a catch can device. But come to think about it, I am not getting any oil in the catch can.

I will check the PVC valve for proper operation. And verify the catch can setup is pulling a vacuum. No vacuum on the crankcase would cause the same thing right?

 

[2L8IW1N]

I don't get any oil in the passenger side PCV either... But the drivers side is a whole other story. I can't believe the amount of oil sucked through there.

 

[a94cobra]

Update: I re-checked the PVC. I can't blow on it at all in the one direction and can blow just fine the other way. So I would conclude it works just fine.

 

[JKD]

Update: I re-checked the PVC. I can't blow on it at all in the one direction and can blow just fine the other way. So I would conclude it works just fine.

You can also not run a PVC at all and put a breather on it to ventilate the crank case pressure.

 

[04SVTCobraSVT04]

A PCV valve popping out is a sign that your crank case is being pressurized under boost. There are two potential causes for this:

1) You have a cheap PCV valve that doesn't have a check valve incorporated into it. If you blow on the hose connected to the PCV valve, does it go through the PCV valve? If so, your blower is doing the same thing and pressurizing your crank case under boost. You can either put a check valve between your PCV and intake manifold or buy a PCV valve from something that was boosted from the factory (like an 03-04 Cobra).

In most cases, the PCV valves that you would buy at the parts store are inadequate at preventing boost from going into the crank case. I had a twin turbo with this problem and I installed a PCV valve from an '88 TurboCoupe and that fixed it.

2) Piston ring blow-by. Just hope your problem is the first one. The fix for this is a rebuild.

Is it possible to have enough blow-by to pop out the pcv and not produce smoke out of the tailpipes?

 

[StngStr]

Is it possible to have enough blow-by to pop out the pcv and not produce smoke out of the tailpipes?

Good question, especially since he says that the PCV is working properly. If the PCV is working properly, it woudl have to be some very serious blow-by to pop the PCV out. With that much blow-by, you would have big problems. Not sure about the smoke out the tailpipes though. Because if there is blow-by, it's going INTO the crankcase from the cylinders, not FROM the crankcase into the cylinders and then out the exhaust.

:shrug:

 

[04SVTCobraSVT04]

Yeah, either way there have been people who have had trouble with running the pcv on 5.0s with boost.

Just do a compression check on each cylinder and make sure everything is good before you decide what to do.

 

[a94cobra]

Compression check is 1st on the list.

I did have the VC breather. I was trying to put the system back together without that. It smoked alot out of the breather.

Another thought I had...I still have the smog controls on the car. Could you somehow tie the PVC line into the smog pump line. It simply sends air down to the exhaust?

You can also not run a PVC at all and put a breather on it to ventilate the crank case pressure.

So just cap the PVC line?

 

[04SVTCobraSVT04]

Mine is doing the same (smoking from the breather!). I think we may have some beautiful blow-by

 

[a94cobra]

how many miles you got?

 

[hardcore35th]

Is anyone running a Procharger or other type centri blower with the PCV and catch routed before the blower? I would think it needs to be this way to work.

 

[a94cobra]

Mine is that way, but it isn't working. I may not have something right. And that is the reason I am here.

 

[hardcore35th]

I have mine pulling vaccum at the plenum, when not under boost, but when its under boost, it closes the PCV. At this point it is releasing out the breather, on the other valve cover. Im idling just fine, and not blowing oil all over the place, and not pushing out gaskets or anything so I guess im fine, as long as im not getting oil in the intake.

 

[wojowojo16]

IT IS PCV, not PVC

PVC is Plastic Plumbing Material.

 

[wojowojo16]

I have a PCV on both valve covers running to the intake prior to the procharger, works just fine and no oil. I was thinking about just having them run under the car and dump under the K-Member, may leave some oil on the underside of the car but not a big deal.

I do have them going through oil seperators.

 

[OneFastSnake]

Running 12 lbs vortech blower and im having no issue, Im also running a SVO PCV, those car come stock with turbo so I figured get one thats ment for boost.