TrailBlazer 4WD L6-4.2L VIN S (2002)
Fuel Pressure Regulator: Description and Operation
Fuel Pressure Regulator Assembly
The fuel pressure regulator is a diaphragm relief valve. The diaphragm has fuel pressure on one side and regulator spring pressure on the other side. The
fuel pressure regulator maintains a constant pressure differential across the fuel injectors under all operating conditions.