The Fuel Injector service process starts with opening the fuel filler cap to release the Fuel Tank vapor pressure followed by removing the engine cover and resonator with the air inlet duct from the
Throttle Body. You should first remove the Brake Booster Vacuum Hose alongside its
Intake Manifold connector before taking out the central sequential fuel injection (CSFI) fuel metering body electrical connector. Remove
Spark Plug Wires from Distributor Cap on cylinders 1, 3, 5 followed by fuel system pressure relief and fuel pipe disconnection at the rear of the intake. Secure the fuel line bolt while keeping all fuel pipe o-rings, washers and spacers properly positioned before removing nuts and clamp from the fuel pipe. First tighten the j 44466-12 and j 44466-13 installed to the metering body before applying the j 44466-1 to the fuel pipe and re-tightening it. First apply the j 41413 to shut the tank valve and extract the regulator system and obtain the j 44466-10 component from the j 41413 tank. Screw the j 44466-10 hose to the j 44466-12-metering body. Then attach the j 39021 along with its companion j 39021-210, j 39021-301 to the electrical connector. Adjust the j 39021 amperage selector to 0.5 amps before continuing. Open both tank valves along with j 44466-10 and pressurize the fuel system until it reaches at least 150 psi pressure. You should confirm each injector function by using the j 39021 while observing pressure drops. The j 41413 should receive its pressure valve closed before venting pressure from the j 44466-10 and disconnecting the j 44466-12 and j 41413. Disconnect the j 39021-301, j 39021-210, and j 39021 from the metering body after which the vehicle electrical connector can be reinstalled. Installation of the Brake Booster Vacuum Hose and ignition wires must be followed by the resonator and air intake duct. Fit the j 38500-a canister by closing its bottom valve and filling it with regular unleaded gasoline plus the top engine cleaner gm p/n 12346535 product. Use the j 38500-a to suspend it while connecting the hose to the j 44466-12 service port. Then open the canister valve at the bottom before attaching a shop air source at the top fitting by adjusting the regulator to 75 psi. Allow the vehicle to run until the canister empties completely before extracting air supply and depressurizing the j 38500-a. Proceed to detach the hose from the j 44466-12, extract both the resonator and air inlet duct as well as ignition wires. After bleeding residual pressure through the j 44466-12, workers should remove the j 44466-13 and j 44466-12 from the metering body next to then disconnect the j 44466-1 from the fuel lines while making sure all components like o-rings, washers, and spacers stay in their appropriate place. The fuel pipe installation procedure includes attaching it to the metering body using a clamp with nuts and tightening these components to 3 nm (27 lb ft) while applying threadlock gm p/n 12345382 to the fuel pipe bolt prior to installing it to 6 nm (53 lb ft). Perform the installment of the Brake Booster Vacuum Hose and connector and the resonator with accompanying air inlet duct as well as ignition wire connection. The engine cover needs replacement while professionals should add one ounce port Fuel Injector cleaner gn p/n 12345104 (or P/N 12345515 in Canada) into the Fuel Tank for each gallon of gasoline. Tell the customer to use the remaining bottle during its next fuel fill-up and suggest them to switch their fuel brand. After start-up check for leakages while having the Fuel Tank filler cap hand-tightened. Then use a tech ii scan tool to review and clear powertrain diagnostic trouble codes (DTCs) before disconnecting it.