1998 3RZ: too much crankcase pressure?

[98Base4R]

I topped off the oil, and then took a little spin with my oil cap sitting on the valve cover (not screwed on). About 1/2 quart of oil sprayed all over the place.

I cleaned up the mess, but it got me thinking: could too much crankcase pressure be causing the Valdez class oil leak? There is plenty of pressure coming out of the oil fill hole when the engine is idling. The PCV valve is doing its job, with strong suction.

Is there a possible cause to this issue that would be economical to fix? I was motivated to reseal the timing chain cover, until I saw that one of the steps is to "remove the head".

Besides the large puddles of oil when I park, it runs great.

Any advice would be appreciated.

 

[Grenvilleter]

Put the oil cap back on. That should fix your problem !

Perhaps I misunderstood your question ?
It spews other places when the cap is on and leaves puddles in your driveway?

 

[98Base4R]

Perhaps I misunderstood how the PCV system was supposed to work.

I thought that the crankcase was supposed to be slightly de-pressurized, or operate at a slight vacuum. Further, excessive oil and vapor coming out of the fill cap hole would be worn rings or a faulty PCV.

 

[Grenvilleter]

You are correct in how/what the PCV does but with the oil cap removed, it cannot function as designed.

Of course there is going to be oil spray if you run the engine without a oil cap on it. Was your PCV valve plugged up initially? If so replace it and then check the new one to see if it plugged after a few miles and go from there.

Does the engine smoke excessively out the exhaust indicating bad rings? A hole blown through a piston would certainly cause excessive pressure in the crankcase but you certainly know something was wrong besides "a puddle of oil" underneath.