An engine needs oil to work properly so checking your oil regularly is a sound practice. You should check the oil level each time you add fuel to your vehicle. On the Pontiac Bonneville, you just have to check the markings on your dipstick to determine how much oil you have.
Read the Oil Dipstick
Park your Pontiac Bonneville on a level surface and wait a few minutes but not too long. You want to avoid waiting too long after the engine is shut off because the oil needs to be warm for accurate readings.
Pop your hood open by opening the release latch and locate your oil dipstick. It’s on the driver’s side close to the center of the engine. It has a looped handle making it easy to grab and it’s located near the back of the engine.