GM 12593231
Fuel Rail

Before starting the replacement of the fuel injection Fuel Rail assembly researchers should never neglect the step of relieving high side fuel system pressure with ch 48027 or by alternative methods. After accomplishing this step disconnect the engine wiring harness electrical connector from the Fuel Injector wiring harness. Empty the Intake Manifold after which the Fuel Injector insulator comes out and you must detach the engine wiring harness electrical connector from the high pressure Fuel Pump. Empty the intermediate fuel pipe before disconnecting wiring connectors from each Fuel Injector piece of hardware. Use a socket wrench to remove the Fuel Rail bolts then extract the Fuel Rail with care while keeping in mind that installers could be inserted with it. To extract an immovable Fuel Injector first remove the clamp then employ tools j-37281-a and j 2619-01 to perform a direct removal procedure without any twisting of the injector. After Fuel Injector extraction the technicians should perform a cleaning procedure and rebuild operations. The installation of Fuel Rail requires lubrication to threads and sealing cone, using gm p-n 12345610 (Canadian P-N 993193) or equivalent silicon-free engine oil gm p-n 12345610. Also treat the fuel injection Fuel Rail Fuel Pressure Sensor in the same manner before tightening both parts to 33 nm (25 lb ft). Place the Fuel Rail along with its injectors into the Cylinder Head while installing the exterior Fuel Rail screws with hand-tight force before finally installing the remainder of the bolts. Use snug torques on the specified sequence when attaching Fuel Injector wiring harness electrical connectors to fuel injectors before tightening the Fuel Rail bolts to 22 nm (16 lb ft). You must place and fasten the intermediate fuel pipe in place and then link the engine wiring harness electrical connector to the high pressure Fuel Pump before installing the Fuel Injector insulator together with the Intake Manifold. Complete the connection of engine wiring harness electrical connector to Fuel Injector wiring harness electrical connector then activate ignition for leak detection before installing the low side fuel pressure service port cap and fuel fill cap and air cleaner assembly.

Install the fuel rail bolts and tighten to 10 Nm (89 lb in).

Position them downward.

Disconnect the fuel injector harness connectors.