Wrangler 4WD L4-150 2.5L VIN P MFI (1998)
Fuel Pressure Pulsation Damper: Description and Operation
Fuel Rail/Fuel Damper
The fuel rail supplies the necessary fuel to each individual fuel injector and is mounted to the intake manifold. A fuel damper is located at the front of the
fuel rail. The damper is used only to help control fuel pressure pulses from the fuel pump. It is not used as a fuel pressure regulator. The fuel pressure
regulator is not mounted to the fuel rail on any engine. It is located on the fuel tank mounted fuel pump module. Refer to Fuel Filter/Fuel Pressure
Regulator in this group for information.
Two different types of dampers are used. The first type is equipped with a vacuum fitting. A vent line connects this vacuum fitting to the intake manifold.
This vent line has no control over fuel system pressure. The second type of damper will not have a vacuum fitting or vent line.
Depending on vehicle model/engine, the fuel rail may/may not be equipped with a fuel pressure test port. Refer to the Fuel Pump Pressure Test for
additional information.
The fuel rail is not repairable.