Excessive Engine Oil Consumption

Diagnostic procedure 

1. Check for oil leaks.
2. Check for worn valve guide(s) or worn valve seal(s) .
3. Check for a damaged or worn piston ring(s) .
4. Check for damaged or worn engine internal parts (cylinder wall, pistons, etc.) .

Also check for 

Check the maintenance records as engine oil that is worn out burns off at a higher rate