Where is the fuel pressure on 1999 Chevy s10 4.3?

There isn't a single, easily accessible fuel pressure test port on a 1999 Chevy S10 4.3L. You'll need to use a fuel pressure gauge with the appropriate fitting to connect to the fuel rail itself. This usually involves disconnecting a fuel line or using a special fitting that screws into a test port on the fuel rail. You will need to consult a repair manual specific to your 1999 Chevy S10 4.3L to find the exact location and procedure. The location varies slightly depending on the exact engine configuration and year.

Important Safety Precautions:

* Disconnect the negative battery cable before working on the fuel system.

* Fuel is highly flammable. Work in a well-ventilated area and avoid sparks or open flames.

* Fuel under pressure can be dangerous. Release pressure carefully according to the instructions in your repair manual.

* Wear safety glasses.

A repair manual (either a physical book or a digital version) is crucial for this task. It will have diagrams showing the fuel rail and the best location for connecting the gauge. You can often find these manuals online or at auto parts stores.