I had an Isuzu Rodeo with a GM 3.2 engine that had small oil flowback holes. When carbon would build up, oil couldn't flow back into the sump and would get burned off, consuming a lot of oil
I researched and someone suggested using the hose for the brake booster to sip the liquid (or spray from the aerosol can) into the hose. This apparently brings the Seafoam directly into the intake plenum and cleans the inside. I don't understand how it worked, but when I did that before every oil change my oil consumption went from about 1.5 quarts every 3,000 miles to no noticeable oil consumption at all.