What is the first thing to check when starting a gasoline engine?

Checking the oil level is crucial before starting a gasoline engine for several reasons. The engine's oil lubricates critical components, reducing friction and preventing wear and tear. If the oil level is low, inadequate lubrication can lead to severe engine damage, including overheating, increased wear, or even complete engine failure. By ensuring that the oil is at the correct level, you help protect the engine and promote its longevity and performance.

While checking the fuel level, battery condition, and coolant level are also important steps in ensuring the engine runs smoothly, they come after confirming that sufficient oil is present. Without adequate oil, the engine shouldn't be started, regardless of the status of other factors.