You need to open the line at the fuel rail from the pump and install the gauge there. When you rent the tester, it has all the instructions for this procedure.
1. Fuel system pressure must first be released before performing this test.
2. Disconnect the 5/16 fuel supply hose from the engine fuel line. Connect fuel system pressure gauge between fuel supply hose and engine fuel line.
Roy
Monday, June 29th, 2020 AT 4:53 PM