My friend has a 2006 2.4L Honda Accord with ~252,000 miles with a manual transmission and its burning a quart of oil every 1,000 miles or so in the winter. It is running 5-w20 Mobil-1 high milage oil and a Mobil-1 Oil filter, both changed every 3,000 to 5,000 miles. We put some oil dye to check for leaks, and we haven't found any. We put a catch can linked to the PCV and it seems to be dumping oil, so we replaced it with a new OEM. It is still dumping oil out, and the dip stick occasionally pops out. Without the catch can, black smoke blows out the back at higher rpms.

Another friend's 2015 2.4L Honda Accord with ~121,000 miles with a manual transmission and the same symptoms, only without the black smoke (dipstick is still popping out, its dumping oil out of the PCV, and not leaking).

I assume its excess oil pressure, although I haven't metered either yet, and no oil light has come on. What could be the problem, and how could we go about solving it?