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Help with PCV system please

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I have an 85' GL non-turbo wagon with 140,000 miles (stock carbureted). It runs great, but has had an issue with oil getting into the air filter housing (especially going around corners). The driver-side PVC hose coming off the valve cover is going to the t-fitting which connects to the PCV hose/valve. There doesn't appear to be much, if any suction to the driver-side hose unless the other side of the t-fitting is plugged off. Is this normal? The other side of the t-fitting has a smaller hose, which goes to the air filter housing and looks to be designed to suck fresh air from the housing. Perhaps the suction increases at higher rpms with the small side of the t-fitting uncapped. Is this normal?


I noticed the other day, while inspecting the passenger side hose that this pictured green plug was inside of the hose and popped out when I removed the hose from the air filter housing. The plug is soft rubber and is about the same diameter as the inside of the hose. I also found, inside the hose, a couple of pieces of black electrical tape that I'm guessing the PO wrapped around the plug. I thought that the PO had put the plug in the hose for some monkey reason, so I removed it and drive around with no ill effect until I took a long high-speed left turn which resulted in a quart of oil in my air-filter housing. Wtf? Is this plug stock? If so, where is it supposed to go?


With the motor running, pressure can be felt coming from the passenger side hose/valve cover, but not the driver side. Is this normal? With the PCV valve sucking (small end of t-fitting plugged), no air is being pulled through the passenger side hose, but rather a decrease in pressure blowing out of the passenger side. Is this normal.


I'm at my wit's end with this issue. Anyone know of a good old-school Suby mechanic in or near Yakima? The guys at my local dealer did not impress me as knowing anything about the EA82s.




Edited by Radio Flyer
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Looks like it was plugged to stop the quart of oil in the air cleaner at high speed problem.


Is your PCV working (the valve)


a couple of links with diagrams for how the plumbing should work






note both links are for engines running webers but the diagrams should be useful.



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hose setup sounds fine, but make sure that the hose on the passenger side isn't plugged, thats the air inlet so its important that its not restricted.


all the oil runs to the left side when cornering, and the car will drink it if the suction on the line is too high.  the small hose allows fresh air in and out so that the suction isn't too strong and theres a vent for pressure on that side.  if you put your finger over the small hose end and increase the throttle you should feel it become a suction.


best guess is a non subaru pcv valve.  the generic ones from parts stores will thread in but create too much suction.  get a subaru direct pcv valve.  its about $7.

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I'd be checking the condition of all the breather hoses to ensure not blocked at all with carbon crud - includes rocker cover removal and wash through the breather baffles with a solvent. A catch can is a great thing for this problem if it continues after inspection and clean up.

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