Service Procedure
Step 1: System CheckUse Strategy - based diagnosis listed in the front of the Driveability and Emissions section of the workshop manual. If the SCPI system is operating properly, inform the customer that the vehicle does not have the condition listed in the owner letter. If poor driveability conditions persist, inform the customer that any further diagnosis and repairs will be at the customer's expense (if the vehicle is outside the parameters of the new vehicle warranty).
Step 2: SCPI Injector Cleaning Procedure
If diagnosis leads to sticking poppet nozzles, follow the service procedures below.
1. Loosen the fuel filler cap to relieve vapor pressure in the fuel tank.
2. Remove the Positive Crankcase Ventilation (PCV) clean air tube from the air inlet tube and set aside.
3. Remove the bonnet and inlet tube from the throttle body.
4. Remove the brake booster vacuum hose and connector from the intake manifold.
5. Remove the electrical connector from the CSFI fuel metering body.
6. Remove ignition wires 1, 3, and 5 from the distributor cap.
7. Remove the fuel line bolt (4) at the rear of the intake manifold. (Figure 1)
8. Relieve the fuel system pressure at the service fitting on the fuel line. Use a shop towel to contain any fuel that may exit the service fitting.
9. Remove the nuts (1) and clamp (2) from the fuel pipe. (Figure 2)
10. Remove the fuel pipes from the metering body. Be careful not to disturb the 0-rings, washer, and spacer in the metering body. (Figure 2)
11. Install the J 44466-12 (2) and the J 44466-13 (1) to the metering body and tighten. Make sure that the fuel pipe 0-rings, washer, and spacers are present and in their proper position. (Figure 3)
12. Install the J 44466-11 (4), clamp (2), and J 44466-13 (1) to the fuel pipe and tighten. (Figure 4)
13. Obtain a nitrogen tank, close the valve (2) on the tank, and remove the regulator assembly. (Figure 5)
14. Install the J 44466-10 (5) to the nitrogen tank(3). The J 44466-10 regulator is preset to 150 psi. (Figure 5)
15. Connect the J 44466-10 hose (1) to the J 44466-12(3). (Figure 6)
16. Install the J 39021 Injector/Coil Balance Tester, the J 39021-210 Injector Tester Adapter Box, and J 39021-301 V6 Fuel Injector Test Adapter (1) to the metering body electrical connector.
17. Adjust the amperage selector switch on J 39021 to 0.5 amps.
18. Open the valve (2) on the nitrogen tank (3). (Figure 7)
19. Open the valve (4) on the J 44466-10 to pressurize the fuel system. The minimum pressure required on the gauge (6) is 150 psi. If 150 psi is not obtained, the tank (3) must be refilled prior to performing this procedure. (Figure 7)
20. Close the valve (4) on the J 44466-10. (Figure 7)
21. Energize one injector using the J 39021. Observe a pressure drop on the gauge (6) and verify the injector/poppet valve operation. An injector/poppet that is "stuck" and not operational will have no pressure drop on the gauge. If an injector remains "stuck" repeat the procedure multiple times (as required) until the injector is operational.
22. Repeat steps 19, 20, and 21 for each individual injector to verify that all injector/poppet valve assemblies are "unstuck" and functional.
23. Shut off the pressure valve (2) on the nitrogen tank (3). (Figure 7)
24. Bleed off the pressure at the J 44466-10.
25. Disconnect and remove the J 44466-10 (5) from the J 44466-12, and the nitrogen tank.
26. Remove the J 39021-301, J 39021-210, and J 39021 from the metering body.
27. Install the vehicle electrical connector to the metering body.
28. Install the 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 air inlet bonnet to the throttle body, and tighten the wing-nut.
31. Install the PCV fresh air tube to the air inlet tube.
32. Obtain J 35800-A (2). Make sure the valve at the bottom of the canister (3) is closed. (Figure 8)
33. Remove the canister top and add 24 ml (0.8 fl. oz.) Top Engine Cleaner, to the canister.
34. Fill the remainder of the canister with regular unleaded gasoline and install the canister top.
35. Suspend J 35800-A from a convenient under hood location.
36. Connect the hose from J 35800-A to the service post on the J 44466-12.
37. Open the valve (3) at the bottom of J 35800-A.
38. Connect a "shop air" source to the fitting at the top of J 35800-A and adjust the regulator (1) to 75 psi.
39. Start the vehicle. It may be necessary to re-adjust the J 35800-A pressure regulator to maintain 75 psi.
40. Let the vehicle run at idle until the canister is empty and the vehicle stalls.
41. Remove the shop air supply from J 35800-A.
42. Depressurize the J 35800-A.
43. Disconnect the J 35800-A hose from the J 44466-12.
44. Remove the PCV clean air tube from the air inlet tube and set aside.
45. Remove the bonnet from the throttle body, and set aside.
46. Remove the ignition wires 1, 3, and 5 from the distributor cap.
47. Remove the brake booster vacuum hose and connector from the intake manifold.
48. Bleed the residual pressure from the J 44466-12.
49. Remove J 44466-13 (1) and J 44466-12 (2) from the metering body. (Figure 9)
50. Remove J 44466-13 (1), clamp (2), and J 44466-11 (4), from the fuel pipe (3). (Figure 10)
51. Install the fuel pipe (3) to the metering body. Make sure that all of the 0-rings (6 and 8), washers (7), and spacers (5) are present and in their proper position. (Figure 11)
52. Install the clamp (2) and nuts (1), and torque nuts to 3 N.m (27 lb in). (Figure 11)
53. Apply threadlock or equivalent to the threads of the fuel pipe bolt (4). Install the fuel pipe bolt and torque fuel pipe bolt to 6 N.m (53 lb in). (Figure 11)
54. Install the brake booster vacuum hose and connector to the intake manifold.
55. Install the bonnet and air inlet tube to the throttle body.
56. Install the PCV fresh air tube to the inlet duct.
57. Install ignition wires 1, 3, and 5 to the distributor cap.
58. Add one (1) ounce of Fuel System Treatment, to the vehicle fuel tank for each gallon of gasoline estimated to be in the tank. Instruct the customer to add the remainder of the bottle of Fuel System Treatment to the vehicle fuel tank at the next fill-up.
59. Tighten the fuel tank filler cap.
60. Start the vehicle and check for fuel leaks.
61. Using the Tech 2 scan tool, check for any stored Powertrain DTC codes. Clear codes as required.
62. Disconnect the Tech 2 scan tool.
63. Advise the customer to change brands of fuel.
Step 3: Replacement of SCPI fuel assembly
If after cleaning the SCPI poppet nozzles, the normal service manual diagnosis still indicated that the SCPI is the cause of the customer complaint, refer to the appropriate Workshop Manual to replace the SCPI fuel assembly.