Ford Powerstroke Mobile Mechanic Orange County Diesel Repair
The part in the picture below is the HPOP oil rail that sits on top of the injectors, which are computer controlled by a separate module called a FICM (Fuel Injection Control Module). The Powertrain Control Module (PCM) sends commands to the Injection Pressure Regulator (IPR) to modulate the amount of oil pressure in the rails that act on the injectors to force fuel into the cylinders at up 40,000 psi!