Oldsmobile PCV Full Of Oil After Intake Gaskets Replaced

Is a wet and oily PCV valve & housing internally a normal condition on the 3800 V6 or is there something wrong? I just replaced intake manifold gaskets along w/ new upper intake plenum (includes new PCV valve + housing), on 1997 Oldsmobile Regency 3.8, due to gasket failure & coolant in cylinders / crankcase. Oil was changed. Car started up fine with white smoke for 10 minutes which then went away after a short time of driving. Something is just not right with the car. Checked all of the spark plugs, they look fine. Checked PCV and found wetness. Checked my 1997 Pontiac Bonneville with th same 3800 motor to compare and found it to be dry with only light varnish stains. Could this be residue from the crankcase or is there still a leak somewhere or some other problem ?

ProTech: I would really check or replace both o-rings for the PCV valve. Usually the only way it gets excessively oily is from one of the two o-rings being cut, torn, or out of place. Or possibly the tube inside the upper intake is not attached properly.

They are both new + the snot is coming thru the pcv valve.

I understand that, but new doesn’t mean they are installed properly, or could have come dislodged. Maybe try another 3800 PCV valve as well. Trust me, I’ve seen this problem a thousand times. 99% of the time, it’s the valve or the o-rings. Do you have the spring in place on top of the valve?

Spring is in place, as well as the tube. Doesn’t the crankcase fumes come up thru the intake, thru the pcv, and into the upper intake plenum ? I am thinking the coolant is in with the crankcase fumes and is condensing in the PCV housing, being relatively cooler than the internal engine. If this is possible, is there a way to pinpoint where it might be coming from ?

If you’ve got coolant still mixing with oil, you either installed the intake gaskets wrong, or got the wrong gaskets all together. Or you’ve got a completely different problem such as a bad head gasket or cracked block/head.

I see no signs in the oil, exhaust, or plugs and that’s why i am baffled and wondering if it is just residue from the major leak that didn’t get cleaned out yet and is working it’s way out. Or those items you listed also crossed my mind, but don’t know how to pinpoint those without pulling the heads (which would not show block problem anyways, would it ?) (did compression check. b4 repairs and saw no issues there, so initially ruled out head gasket).

A compression check is not a real good way to check for a blown head gasket. More often than not it is compression that is getting into the cooling system from the cylinder. You really need to do a leakdown test, but that requires a special leak down tool and compressed air. Let me ask you this…is it using oil now that you’ve done the repairs? After driving it the 20 miles or so, did you notice a drop in oil level?

Oil level is constant, not up or down. now am up to 120 miles. initially coolant level was dropping every day, but found a small leak in overflow hose today and replaced it, so now need to monitor more.

If the coolant level was dropping every day, did you notice a puddle on the ground? The hose might not be your only issue with that! Could be a head gasket problem like I mentioned earlier.

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