Wondering if a cheap PCV Valve like a Fram would cause oil to be in the Plenum due to incorrect spring pressure?

 

Frams are usually not cheap. If the Fram PCV is leaking oil into your plenum then I'm gonna have to go out and get another brand since I'm using a fram PCV.

 

You will get some oil slime build up in the plenum because the pcv
pulls oil vapor from the valve cover and it generaly condenses
on the inside of the plenum causing the sooty stuff you see.

If you are getting actual oil up there then yes, the PCV is holding
open too much. You would be supprised at the number of different
valves there are. Best bet would be to use a genuine GM unit.

 

The way it was explained to me goes something like this. A PCV Valve has to have "x" amount of spring tension and the amount of tension is dependant on the type of motor hence the need for so many various Valves. Going with Cheaper PCV Valves they do focus as much on the correct amount of tension on the spring as as it's a "fit". By not having the correct amount of tension on the spring can cause the valve to not close completely under heavy vaccum (I might have that backwards) which can cause the vaccum to pull up into the Plenum along with some oil. As I said I might have gotten it backwards as I'm no mechanic but it sounds logical to me especially after knowing what I do about their Oil Filters. Any Comments?

 

LOL you posted as I was typing my post. So I was right but you explained it better. Could this be what is causing oil to get on my IAC?

John

 

Are you getting oil standing on the plenum floor? You can expect
some oil film, that is normal.

 

As you stated it's more of a film that has coated the inside of the plenum and the IAC motor. About every month or so I have to remove my IAC and clean it due to the oil residue around the tip which causes me to sometimes have a rollercoaster idle. After I talked to my brother who ownes a Napa Auto Care Center and he was telling me about the PCV issue above I started giving it some thought as it might be a culprit.

 

That sounds like it. If you need to clean it every month it's not
working properly. Get a real Delco one and you should be ok.

You may also want to check the EGR operation. That can also soot
up the IAC.

 

Thanks Swapmaster you have been a big help. I replaced my EGR Valve, EGR Temp Sensor, and EGR Solenoid about 5 months ago. I agree that changing the PCV Valve to a AC Delco version might help if not eliminate the problem. If not it's no big loss. Thanks Again.

John

 

Since you have taken the EGR question out of the equasion the
Delco unit WILL take care of it.

Take it easy.

 

what about just eliminating the PCV valve and putting a breather on the valve cover and plugging the hole on the intake

 

so are you guys saying that if your PCV valve isn't working properly, then that could afect my EGR valve??????



87 350 TPI-TTOP

 

That's a good question and I didn't know the answer either so I thought I'd search for more info and this is what I found.

http://www.hastingsfilter.com/engine...tsb_94-2r.html

 

There is no mention of the PCV Valve effecting the EGR. Swapmaster was saying that the EGR can effect the IAC.