What would cause about a 1/2 quart of oil to magically appear in an engine? I've changed the oil twice adding right amount to only see an additional 1/2 quart more when checked few days later

 

If your engine is making oil, then most likely that 1/2 quart is coolant that is mixing with your oil due to a head gasket leak.

 

I don't think its a head gasket leak. I'm not losing coolant, seeing any white smoke, and the oil doesn't look milky. The car was sitting for a while could the oil have clumped and now is dissolving and adding to the new oil?

 

not changing the oil filter might do that.

I dont think oil clumps, sludged oil would but that would be so much sludge!

i dunno