Loop your finger through the handle at the top and gently pull the Pontiac Bonneville dipstick out of its sheath. Use a rag or tissue to wipe it clean.
Observe the “X” marks on the dipstick. These mark the safety zone for the safe running of your engine.
Slip the dipstick back into the sheath and pull it out immediately to get a clear reading. Check the oil level on the dipstick without wiping it off.
Drain some oil out if the oil reads over the top marking on the dipstick. The mark should be within the safe range on the dipstick. If it is at or below the bottom safe marks, add oil until level lies between the safe marks.