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Fuel Injector Cleaning Procedure

WARNING: This page is about a different variant/trim than selected.

Tools Required

  1. Loosen the fuel fill cap to relieve vapor pressure in the fuel tank.
  2. Relieve the fuel system pressure.
  3. Remove the positive crankcase ventilation (PCV) clean air tube from air inlet duct and set aside.
  4. Remove the resonator and air inlet duct from throttle body.
  5. Remove the brake booster vacuum hose and connector from intake manifold.
  6. Remove the electrical connector from the central sequential fuel injection (CSFI) fuel metering body.
  7. Remove the spark plug wires from 1, 3 and 5 from the distributor cap.
  8. Remove the fuel feed pipe bracket stud (3).
    Fig 1: Removing Fuel Feed Pipe
    GM1655473Courtesy of GENERAL MOTORS CORP.
  9. Remove the fuel pipe retainer nuts (2) and retainer (1).
  10. Remove fuel feed pipe (4).
    11. IMPORTANT: Make sure that the fuel pipe O-rings, washers, and spacers are present and in their proper position.
    Fig 2: View Of J 44466-12 & J 44466-13
    GM648221Courtesy of GENERAL MOTORS CORP.
  11. Install the J 44466-12  (2) and the J 44466-13  (1) to the metering body and tighten. See Special Tools .
  12. Install the J 44466-11  , retainer, and J 44466-13  to the fuel feed pipe and tighten. See Special Tools .
  13. Obtain the J 41413  , close the valve (2) on the tank (3), and remove the regulator assembly. See Special Tools .
    Fig 3: View Of J 44466-10, J 41413 & Tank
    GM648216Courtesy of GENERAL MOTORS CORP.
  14. Install the J 44466-10  (5) to the J 41413  tank (3). See Special Tools .
  15. Connect the J 44466-10  hose (1) to the J 44466-12  (3). See Special Tools .
    Fig 4: View Of J 44466-10, J 44466-12, J 39021, J 39021-210 & J 39021-301
    GM648224Courtesy of GENERAL MOTORS CORP.
  16. Install the J 39021  , the J 39021-210  and J 39021-301  (4) to the metering body electrical connector. See Special Tools .
  17. Adjust the amperage selector switch on J 39021  to 0. See Special Tools .5 amps.
  18. Open the valve (2) on the tank (3).
  19. Open the valve (4) on the J 44466-10  to pressurize the fuel system. See Special Tools . Then close valve (4) before firing injectors.
    Fig 5: View Of J 44466-10, J 41413 & Tank
    GM648216Courtesy of GENERAL MOTORS CORP.
    IMPORTANT: The minimum pressure required on the gage (6) is 150 psi. If 150 psi is not obtained, the tank (3) must be refilled prior to performing this procedure.
  20. Fire one injector using the J 39021  . See Special Tools . Observe a pressure drop on the gage (6) and verify the injector/poppet valve operation. An injector/poppet that is stuck and not operational will have no pressure drop on the gage. If an injector remains stuck, repeat the procedure multiple times (as required) until the injector is operational.
  21. Repeat steps 19 and 20 for each individual injector to verify that all injector/poppet valve assemblies are unstuck and functional.
  22. Shut off the pressure valve (2) on the tank (3) of the J 41413  . See Special Tools .
  23. Bleed off the pressure at the J 44466-10  . See Special Tools .
  24. Install the PCV fresh air tube to the air inlet duct.
  25. Disconnect and remove the J 44466-10  (1) from the J 44466-12  (3) and the J 41413  . See Special Tools .
  26. Remove the J 39021-301  , J 39021-210  and J 39021  from the metering body. See Special Tools .
    Fig 6: View Of J 44466-10, J 44466-12, J 39021, J 39021-210 & J 39021-301
    GM648224Courtesy of GENERAL MOTORS CORP.
  27. Install the vehicle electrical connector to the metering body.
  28. Install brake booster vacuum hose and connector to the intake manifold.
  29. Install ignition wires 1, 3, and 5 to the distributor cap.
  30. Install the resonator and air intake duct to the throttle body and hand tighten wing nut.
  31. Obtain J 38500-A  (2). See Special Tools .
    Fig 7: Identifying Fuel Injector Cleaner
    GM651337Courtesy of GENERAL MOTORS CORP.
    IMPORTANT: Make sure the valve at the bottom of the canister (3) is closed.
  32. Remove the canister top and add top engine cleaner GM P/N 1050002 (Canadian P/N 992872) to the canister.
  33. Fill the remainder of the canister with regular unleaded gasoline and install the canister top.
  34. Suspend J 38500-A  from a convenient underhood location. See Special Tools .
  35. Connect the hose from J 38500-A  (1) to the service port on the J 44466-12  (3). See Special Tools .
    Fig 8: View Of J 44466-10, J 44466-12, J 39021, J 39021-210 & J 39021-301
    GM648224Courtesy of GENERAL MOTORS CORP.
  36. Open valve (3) at the bottom of J 38500-A  . See Special Tools .
    Fig 9: Identifying Fuel Injector Cleaner
    GM651337Courtesy of GENERAL MOTORS CORP.
  37. Connect a shop air source to the fitting at the top of J 38500-A  and adjust the regulator (1) to 75 psi. See Special Tools .
  38. Let the vehicle run at idle until the canister is empty and the vehicle stalls.
  39. Remove the shop air supply from J 38500-A  . See Special Tools .
  40. Depressurize the J 38500-A  . See Special Tools .
  41. Disconnect the J 38500-A  hose from the J 44466-12  . See Special Tools .
  42. Remove the PCV clean air tube from the air inlet duct and set aside.
  43. Remove the resonator and air inlet duct from the throttle body and set aside.
  44. Remove ignition wires 1, 3, and 5 from the distributor cap.
  45. Remove brake booster vacuum hose and connector from the intake manifold.
  46. Bleed the residual pressure from J 44466-12  . See Special Tools .
  47. Remove J 44466-13  (1) and J 44466-12  (2) from the metering body. See Special Tools .
    Fig 10: View Of J 44466-12 & J 44466-13
    GM648221Courtesy of GENERAL MOTORS CORP.
  48. Remove J 44466-13  , retainer, and J 44466-11  from the fuel feed pipe. See Special Tools .
    49. IMPORTANT: Make sure that all of the O-rings (6 and 8), washers (7), and spacers (5) are present and in proper position.
    Fig 11: Installing Fuel Feed Pipe
    GM1655472Courtesy of GENERAL MOTORS CORP.
  49. Install the fuel feed pipe (4) to the metering body.
    50. NOTE: Refer to FASTENER NOTICE .
  50. Install the retainer (1) and retainer nuts (2).

    Tighten:  Tighten the nuts to 3 N.m (27 lb ft).

  51. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489) or equivalent, to the threads of the fuel feed pipe bracket stud (3).
  52. Install the fuel feed pipe bracket stud (3).

    Tighten:  Tighten the stud to 6 N.m (53 lb ft).

  53. Install the brake booster vacuum hose and connector to the intake manifold.
  54. Install the resonator and air inlet duct to the throttle body.
  55. Install the PCV clean air tube to the inlet duct.
  56. Install brake booster vacuum hose and connector to the intake manifold.
  57. Install ignition wires 1, 3, and 5 to the distributor cap.
  58. Add 1 ounce of port fuel injector cleaner GM P/N 12345104 (Canadian P/N 12345515), or equivalent to the vehicle fuel tank for each gallon of gasoline estimated to be in the tank.
    IMPORTANT: Instruct the customer to add the remainder of the bottle of port fuel injector cleaner to the vehicle fuel tank at the next fill up.
  59. Hand tighten the fuel tank filler cap.
  60. Start the vehicle and check for fuel leaks.
  61. Using a Tech II scan tool, check for any stored Powertrain DTC codes. Clear codes as required.
  62. Disconnect Tech II scan tool.
    IMPORTANT: Advise the customer to change brands of fuel.
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