My daughter’s '95 Corolla uses about a quart of oil in 300 miles when she drives on the highway. Around town it doesn’t seem to be a problem. The car does not smoke nor does it leave an oil stain when parked. The compression was 177 to 185 dry and 220 to 225 wet. She recently had a rebuilt cylinder head installed for a burned valve, but this problem predates that. I am guessing PCV valve plug is causing high crank case pressure and forcing oil out around seals at highway speeds. Any other thoughts?
The differences between the dry and wet compression tests indicates a problem with the rings and cylinder walls. Which would result in higher oil consumption at highway speeds because of higher crankcase pressures. The reason it doesn’t smoke is, at highway speeds the converter is hot enough where efficiently burns the oil where no smoke is produced.
But try this. Add a can of RESTORE for 4 cylinders to the engine oil. And if doing this reduces or eliminates the oil consumption, it pretty much confirms there’s a problem with the rings and cylinders.