The replacement process for Fuel Rail assembly requires engine sight shield removal followed by application of gm x - 30a spray engine cleaner to the assembly components but no liquid immersion. After disconnecting the accelerator control cable and cruise control cable from their respective positions on the cable bracket and
Throttle Body, disconnect and remove the upper engine wire harness retainer nut which allows the removal of the evap purge valve harness connector. After positioning aside the upper engine wire harness users must start relieving fuel system pressure. It is essential to match the connectors with their specific injector positions so the engine can activate injectors in the right firing sequence upon assembly completion. Pull each injector connector top section by no more than the white marking to reveal the release tab at the lower side. The technician must disconnect fuel feed pipes and return pipes from the Fuel Rail as well as remove the fuel pressure regulator vacuum line. The crossover tube securing screw to the right Fuel Rail needs loosening for removal of the Fuel Rail mounting bolts followed by extraction of the assembly. The technicians must remove the injector lower o-ring seals which go on each fuel injector. Apply smooth engine oil to new lower o-ring seals then place them at the injector spray tip end before installing the injectors. The crossover tube requires removal along with its o-ring from the right Fuel Rail retainer. Install a new o-ring before lubricating it. Put the crossover tube into the right Fuel Rail before loosely installing the retainer. The Fuel Rail assembly must be mounted to the
Intake Manifold with gm p/n 12345382 thread lock applied to Fuel Rail bolt threads before tightening them to 10 n.m (89 lb in) while right crossover pipe retainer screw reaches 3.8 n.m (34 lb in). Attach all fuel pressure regulator vacuum line components, fuel feed and return pipes to the Fuel Rail and injectors with correct firing order sequence while avoiding wire harness stretch. Place the upper engine wire harness then connect the evap purge solenoid and install the retainer nut by tightening it to 5.5 n.m (49 lb in). Reconnect the accelerator control cable and cruise control cable to their positions at the cable bracket and Throttle Body while installing the engine sight shield mounting bracket with its bolts. After tightening the fuel filler cap you should finish by connecting the negative
Battery Cable. Switch on the ignition for 2 seconds then disable it for 10 seconds before another 2-second ignition switch on to test for fuel leaks before fitting the engine sight shield.