GM 12602113
Fuel Rail

The Fuel Rail assembly replacement requires a first stage to remove the engine cover together with the air cleaner resonator outlet duct. A service part identification number with eight digits exists on the Fuel Rail assembly for maintenance purposes. Use gm x-30a or equivalent engine cleaner to clean the Fuel Rail assembly according to the product guidelines without submerging it in liquid cleaning solutions. First disconnect the accelerator control cable and cruise control cable from their fixings on the cable bracket as well as Throttle Body when available followed by crimping off the cruise control cable engine-end fitting from throttle lever. The servicing technician should remove the upper engine wire harness retainer nut followed by disconnecting the evaporative emission (EVAP) purge valve harness connector before positioning the upper engine wire harness to the side. The fuel system needs decompression while you mark every connector to its specific injector for maintaining the proper firing sequence after assembly. Use pliers only on multec 2 fuel injector connectors as their neckline may become damaged instead. To disconnect a fuel injector connector you should raise the connector position assurance (CPA), depress the tab and then let go of the cpa. Remove the Fuel Rail assembly while supporting it and take caution to protect the electrical connector terminals and spray tips from potential damage. Apply caps to the fittings and insert plugging accessories to stop contamination. Proceed with these installation and removal steps: disconnect the fuel feed and return tubes (1, 2) from the Fuel Rail, remove the fuel pressure regulator vacuum hose, loosen the right Fuel Rail crossover tube screw and untighten the Fuel Rail bolts to separate the whole rail assembly. The bottoms o-ring seals on the injectors need discarding. Lubricate new fuel injector lower o-ring seals using clean engine oil and use them to install each injector one by one. Remove the retaining clip attaching screw along with the crossover pipe retainer from the right-hand Fuel Rail. Afterwards disconnect the crossover pipe rail and its o-ring . The crossover pipe requires clean engine oil lubrication of a new o-ring before installation onto the crossover pipe where it leads into the right Fuel Rail. To avoid thread stripping, initially start the attaching screw with hand power before installing the crossover pipe retainer and screw on the Fuel Rail. Apply gm p/n 12345382 with code 10953489 threadlock to the Fuel Rail bolts and install the bolts by tightening to 10 n.m (89 lb in) and tighten the screw to 3.8 n.m (34 lb in). Zero air leakage by establishing connections of fuel pressure regulator vacuum hose then fuel lines (1 and 2) and fuel injectors with original connectors while regularly rotating each injector to prevent strain on its wiring. Route the upper engine wire harness while joining the evap purge solenoid connector followed by installation of the retainer nut which needs to be tightened to 5.5 n.m (49 lb in torque). If equipped with Throttle Body and cable bracket the accelerator control cable joins with the cruise control cable then the engine-end fitting attaches to the throttle lever. The last step involves installing the air cleaner resonator outlet duct followed by the engine cover while performing a leak check through a two-second engine ignition turn-on followed by a ten-second engine off period then a second engine ignition turn-on to inspect fuel leaks.

The first step to change the Fuel Rail assembly begins with relieving fuel system pressure then removing the wire harness bracket nut. The vehicle requires disconnecting three elements - evap purge solenoid electrical connector and generator electrical connector and manifold absolute pressure sensor and Knock Sensor. Opt for the following steps to detach the electronic throttle control (ETC) electrical connector. Start by releasing the gray retainer and depressing the black clip before separating the connector. Next, remove the Knock Sensor harness connector from the Intake Manifold. Exchange the connector position assurance retainer to remove fuel injectors and main coils from the right side of the motor before proceeding with the left side main coils and fuel injectors by unplugging the harness clips from the Fuel Rail in sequence. Place the engine wire harness to the side after marking which electrical connector belongs to each Fuel Injector for reassembly. First push the tab located on the connector then pull the cpa retainer one click up before completely disconnecting all Fuel Injector electrical connectors. Decouple the positive crankcase ventilation (PCV) hose followed by disconnecting the fuel feed pipe from the Fuel Rail as the first step when removing Fuel Rail bolts. Take out the Fuel Rail assembly while protecting both the injector electrical connector terminals and spray tips and ensure you stop up all exposed fittings to stop contamination. First clean the Fuel Rail by spraying an engine cleaner and afterward remove the lower o-ring seals from each injector. Deliver engine oil to new Fuel Injector lower o-ring seals prior to their installation on each injector component. After applying threadlock gm p/n 12345382 (Canadian P/N 10953489) to 5 mm (0.2 in) of the Fuel Rail bolts' threads, tighten them to 10 n.m (89 lb in). The fuel feed pipe requires attachment to the Fuel Rail along with pcv hose installation before fitting the electrical connectors to the fuel injectors. Pay attention to proper assembly. Begin by placing the engine wire harness followed by joining all main coil and fuel injectors on the left side and then repeating the same process for the right side and finally installing cpa retainers and harness clips to the Fuel Rail . Follow the etc electrical connection process which includes engaging the gray retainer before joining the MAP Sensor and Knock Sensor alongside their respective connectors to the Intake Manifold and resultant connections of the evap purge solenoid electrical connector and generator electrical connector . Complete the installation by fixing the wire harness bracket nut to 5 n.m (44 lb in), screw down the fuel fill cap and connect the negative Battery Cable while evaluating for leaks through a test sequence of on-2 seconds-off-10 seconds-on.

Fuel delivery through the l59 e85 Fuel Rail needs e85 denso fuel injectors which require special maintenance procedures because it works with fuel containing up to 85 percent ethanol. You should start by reducing fuel system pressure then unfastening the wire harness bracket nut. Disconnect first the electrical connector for evaporative emission (EVAP) purge solenoid followed by generator and then manifold absolute pressure (MAP) sensor and knock sensor connectors. The knock sensor harness connector should be removed from the intake manifold while also taking away the cpa retainer and main coil and Fuel Injector connectors. Next step requires dissolving the harness clips from the Fuel Rail area while moving the upper engine wire harness into position. Preventing connector damage requires that you refrain from using pliers to disconnect multec(R) 2 Fuel Injector connectors. The reassembly requires marking the connectors first before using the cpa retainer to lift one click and pushing the tab on each connector while disconnecting them sequentially. The procedure requiresmitters to start by disconnecting the fuel pressure regulator vacuum line, the pcv hose and the fuel feed and return pipes (1, 2) before unbolting the Fuel Rail. Before removing the Fuel Rail assembly users must carefully pull out the component to protect both injector electrical connector terminals and spray tips and apply caps on open fittings to block contamination. Spray type engine cleaners should be used on the Fuel Rail assembly when needed and new Fuel Injector lower o-ring seals require clean engine oil to lubricate before they are installed. The Fuel Rail installation requires threadlocking gm p/n 12345382 or its canadian equivalent p/n 10953489 to be applied on Fuel Rail bolts before tight installation to 10 n.m (89 lb in). After reattaching the pcv hose you must hook up the fuel pressure regulator vacuum line alongside the fuel feed and return pipes (1, 2). The engine wire harness should be positioned before reattaching the Fuel Injector electrical connectors properly. After reconnecting the main coil and fuel injectors the harness clips must be installed onto the Fuel Rail while also installing the cpa retainers. Reconnect the MAP Sensor connector with the knock sensor connector to the intake manifold along with the evap purge solenoid electrical connector and the generator electrical connector. Insert the wire harness bracket nut before fastening it with 5 n.m (44 lb in) torque then secure the fuel fill cap and fasten the negative Battery Cable. Perform a leak examination using this sequence of check: turn ignition on for 2 seconds followed by off for 10 seconds and then turn on once more to detect fuel leaks.

Disconnect the EVAP purge solenoid electrical connector, the generator electrical connector, the MAP sensor, and the knock sensor.

If needed, remove and discard the fuel injector lower O-ring seal from each injector.

Pull the connector position assurance (CPA) on the injector connector up, push the tab on the injector connector in, and release the CPA to disconnect the fuel injector connector.

Remove the wire harness bracket nut and disconnect the evaporative emission (EVAP) purge solenoid electrical connector, generator electrical connector, manifold absolute pressure (MAP) sensor, and knock sensor.

Disconnect the fuel pressure regulator vacuum line, loosen the crossover tube to right fuel rail retainer screw, remove the fuel rail bolts, and then remove the fuel rail.

Install the fuel injectors and retainers (521).

Tighten them to 10 N.m (89 lb in).

Turn the ignition ON with the engine OFF for 2 seconds, then turn it OFF for 10 seconds, followed by turning it ON again with the engine OFF, and inspect for fuel leaks.

Disconnect them, marking them for reassembly, and remove the harness clips from the fuel rail.

Cap the fittings and plug the holes to prevent contamination, then disconnect the fuel feed and return pipes and the fuel pressure regulator vacuum line.