Fuel is the essential food an engine needs to operate. The 4.3-liter V6 engine in the Chevrolet Blazer receives gasoline from the fuel system that is mixed with inlet air in the cylinders and combusted by the spark plugs thousands of times per minute. The fuel system is sealed and pressurized so the fuel can make the trip from the gas tank in the rear to the engine in the front of the Blazer. If you need to check the fuel pressure, the process is not difficult.
Turn the Blazer off and open the hood.
Remove the protective cap from the fuel pressure test port. The port's location depends on the fuel injection type, whether the 1992 to 1995 central port injection (CFI) or the 1996 to 2005 central sequential fuel injection (CSFI)/multiport fuel injection (MFI). The CFI port is behind the intake plenum next to the distributor, and the CSFI/MFI port is about the left valve cover behind the positive crankcase ventilation valve tube.
Connect the fuel pressure gauge to the fuel pressure test port. The system is pressurized, so cover the test port and pressure gauge line fitting with a shop rag. Set the gauge's bleed hose in a container approved for gasoline.
Turn the ignition to on without selecting start and have an assistant look at the fuel pressure gauge. It should read 60 to 66 psi.
Bleed the air from the pressure gauge. Turn the ignition off and wait at least 10 seconds.
Turn the ignition back on without selecting start to cycle the fuel pump, pressurizing the fuel system. Wait 10 minutes, then read the gauge. It should not read less than 5 psi below the initial pressure reading or below 55 psi.
Bleed the system pressure with the gauge until the gauge reads 10 psi. Wait 10 minutes then read the gauge again. It should not read less than 8 psi.
Start the engine and allow it to warm to operating temperature. Depress the throttle pedal momentarily while an assistant reads the pressure gauge. It should not rise above 66 psi.
Turn the engine off. Disconnect the fuel pressure gauge from the fuel pressure test port then remove the shop rag. Replace the protective cap.
Dispose of any gasoline in the container in accordance with local policy.
