What mechanic tool is typically used to test fuel pressure in a gasoline engine?

The tool specifically designed to measure fuel pressure in a gasoline engine is the fuel pressure gauge. This instrument accurately provides readings of the fuel pressure, which is critical for diagnosing fuel system issues. Proper fuel pressure is essential for the engine to run efficiently, as it ensures that the fuel injectors deliver the correct amount of fuel to the engine.

Using a fuel pressure gauge allows a mechanic to determine if the fuel pump is functioning correctly, if there are any restrictions in the fuel line, or if the fuel filter is clogged. This makes it an indispensable tool for troubleshooting performance problems related to fuel delivery.

The other tools mentioned serve different purposes: a wrench is used for tightening or loosening fasteners, a multimeter measures electrical values such as voltage or resistance, and a compression tester assesses the engine's cylinder compression, which is unrelated to fuel system pressure. Understanding the specific functions of tools helps mechanics effectively diagnose and resolve engine issues.