You need to use an appropriate method to first reduce the pressure in the fuel system before starting replacement of the Fuel Rail assembly. First locate the Fuel Rail then disconnect its fuel feed pipe before taking out the
Intake Manifold. Engine cleaners like gm x-30a or equivalent should be used to clean the Fuel Rail assembly and cylinder head by following spray type cleaning instructions without subjecting the Fuel Rail to soaking with liquid solvent. Cut off the
Fuel Injector harness in-line connector from the engine wire harness then take it away from the rocker cover. Remove the Fuel Rail attaching bolts first and extract the Fuel Rail assembly with gentle procedure to safeguard the injector electrical terminals and spray tips by capping the fittings and plugging the holes to stop contamination. Eliminate and dispose of the injector lower o-ring seals from each component. Continue the Fuel Rail installation if replacement is not required. The installation begins with removing the Fuel Injector wire harness from the Fuel Rail before removing the fuel injectors. During assembly process first attach the Fuel Injector harness to the Fuel Rail before installing the fuel injectors. New lower injector o-ring seals require clean engine oil lubrication before their installation on spray tips of each injector as part of the Fuel Rail assembly installation process. After applying threadlock gm p/n 12345382 (Canadian P/N 10953489) or equivalent to a 5 mm (0.2 in) wide area of the Fuel Rail bolt threads you should install the bolts with a torque setting of 10 nm (89 lb in). Stop by attaching the Fuel Injector harness in-line connector to engine wire harness near the rocker cover before joining the fuel feed pipe with the Fuel Rail followed by Fuel Injector electrical connectors. Connect the Intake Manifold while also restoring the negative
Battery Cable. Turn on the ignition while the engine remains off for two seconds before turning off the ignition for ten seconds. Finally check for fuel leaks while once again turning on the ignition with the engine off.