2003 Pontiac Bonneville Owner's Manual - Page 275

Checking Engine Oil It's a good idea to check your engine oil every time you get fuel. In order to get an accurate reading, the oil must be warm and the vehicle must be on level ground. Turn off the engine and give the oil several minutes to drain back into the oil pan. If you don't, the oil dipstick might not show the actual level. Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it again, keeping the tip down, and check the level. The engine oil dipstick is located behind the engine cooling fans and in front of the engine oil fill cap. The top of the dipstick is a round yellow loop. See Engine Comparfment Overview on page 5-74 for more information on location. I I 5-16