The first step for servicing the Fuel Rail assembly involves lowering fuel system pressure while cleaning the assembly with gm x-30a engine cleaner along with other equivalent products without allowing it to sit in liquid cleaning solvent. The service procedure begins with removing the engine sight shield bracket nuts followed by unmounting the bracket and then disconnecting the generator harness connector and evaporative emission canister purge valve harness connector and throttle position sensor harness connector along with the electronic throttle control harness connector. After removing the bracket studs from the upper engine wire harness it should be positioned aside so that each connector can be identified with its matching injector based on firing sequence. Locate the white portion on each injector connector then grip and carefully lift the top section of connectors only until exceeding the white area. Next, press the lower tab to unlock the connector. The process starts by disconnecting both the fuel feed pipe and return pipe from the Fuel Rail as a first step followed by disconnection of the line that supplies vacuum to the fuel pressure regulator. First remove the Fuel Rail attaching bolts then take off the assembly before extracting one injector lower o-ring seat from each injector and discarding its seal. Clean engine oil must be used to lubricate new lower injector o-ring seals before placing them onto each injector spray tip. Install the Fuel Rail assembly to the
Intake Manifold by applying gm p/n 12345382 (Canadian P/N 10953489) threadlock on the 5 mm (0.020 in) band of bolts with a torque of 12 n.m (106 lb in). Reinstall the fuel pressure regulator vacuum line together with the fuel feed and return pipes while verifying correct injector electrical placement for maintaining the engine firing sequence. Attach the upper engine wire harness bracket using its retainer studs and fasten up the nut to 10 n.m (89 lb in). The repair process requires reattachment of the generator harness connector along with the evap canister purge valve harness connector and throttle position sensor harness connector and electronic throttle control harness connector. Secure the engine sight shield mounting bracket bolts to 10 n.m (89 lb in) while tightening the nuts and fasten the fuel filler cap and connect the negative
Battery Cable. A fuel leak inspection process begins with a two-second ignition on, followed by ten seconds of ignition off before repeating the procedure for visual inspection of fuel leakage. Mount the engine sight shield and fasten its bolts with a torque of 10 n.m (89 lb in).