This is a fully CNC machined plug to replace the faulty factory drivers side fuel rail plug. The factory plug is internally spring loaded and after the stress of the fuel pushing on it for a period of time, it fails. This will typically throw a low fuel rail pressure CEL (P0087) and commonly gets diagnosed as a bad fuel system component. Many times, the factory plug is simply opening before it should and causes the fuel rail to lose pressure. This plug will not allow that to happen! This directly replaces the factory, faulty plug and comes with a new o-ring to seal correctly!
This plug will fit 04.5-10 Duramax.