Installation
1. Place new intake manifold from kit upside down on clean workbench.
2. Remove and discard shipping plug from brake booster vacuum port on bottom of intake manifold by pressing release ring toward intake manifold.See Figure 30.
3. Clean and inspect EGR tube O-ring seal.
4. Install EGR tube to new intake manifold. Make sure tab on mounting bracket is in slot on intake manifold.
5. Tighten EGR tube-to-intake manifold retaining bolts to 7-11 Nm (62-97 lb/in).
6. Install fuel line bracket to new intake manifold.
7. Clean EGR bracket and EGR valve mating surfaces.
8. Position three (3) plastic conduit mounting screws in conduit before installing intake manifold. This will ease in the installation of these screws later in the procedure.
9. Install intake manifold as follows:
^ Position intake manifold on top of engine and route CNG fuel supply hose behind subframe. See Figure 31.
^ Raise vehicle.
^ Route CNG fuel supply hose following path of the CNG fuel pressure regulator coolant lines.
^ Lower vehicle.
^ Install new intake manifold-to-cylinder head gasket.
^ Install one of the intake manifold bolts in the intake manifold where right side intake manifold stud was removed. Bolt must be in place before intake manifold is completely installed, due to interference with the alternator bracket.
^ Position intake manifold in installed position.
^ Partially thread installed bolt into head.
^ NOTE:
There is a reinforcing bracket attached to the natural gas fuel rail. This bracket will be anchored by one of the intake manifold retaining bolts.
^ Install remaining intake manifold bolts and stud with nuts. Position stud in position between first and second intake manifold runner.
^ Tighten intake manifold retaining bolts/studs to 16-20 Nm (12-15 lb/ft) Tighten in a standard-type torque sequence.
^ Place shop towel over throttle body mounting plate to prevent foreign material from entering intake manifold.
10. Install plastic conduit to rear of intake manifold with three (3) Torx 25 mounting screws.
11. Connect lead to mega-fuse. Install new mega-fuse into housing, if damaged during removal.
^ Tighten mega-fuse mounting nuts to 10-12 Nm (89-106 lb/in).
12. Connect mega-fuse housing to locator tab on main engine wiring harness.
13. Install mega-fuse cover.
14. Connect three (3) vacuum lines to bottom of throttle body flange.
15. Install new gasket between EGR valve and tube assembly. Install two (2) EGR valve bolts to EGR tube assembly.
^ Tighten EGR tube mounting bolts to 7-11 Nm (62-97 lb/in).
16. Clean camshaft position sensor mating surfaces and O-ring seal.
17. Install camshaft position sensor.
^ Tighten camshaft position sensor retaining bolts to 18-23 Nm (13-17 lb/ft).
18. Connect PCV hose to intake manifold.
19. Clean fuel injector O-rings, then install fuel injection manifold.
20. Install fuel injection supply manifold mounting bolts.
^ Tighten supply manifold mounting bolts to 8-12 Nm (71-106 lb/in).
21. Position fuel charge wiring harness, then tighten retaining screws securely.
22. Connect fuel injector electrical connectors. (Do not switch # 4 injector connector with camshaft position sensor connector. They are the same design).
23. Connect camshaft position sensor electrical connector.
24. NOTE:
Do not allow wiring to run near EGR tube. Route IAC valve electrical connector between # 3 and # 4 intake runners and connect to IAC valve.
25. Install retaining screw to fuel line bracket.
26. Connect vacuum line to fuel pressure regulator.
27. Connect breather hose to valve cover.
28. Install throttle body to intake manifold.
^ Tighten mounting bolts to 8-12 Nm (71-106 lb/in).
29. Raise vehicle.
30. Connect brake booster line to intake manifold.
31. Connect brake booster line to intake manifold.
32. Install new large (1/2") copper washer in regulator outlet line port, then install new compuvalve inlet line. Finger tighten fitting at this time.
33. Install new large (1/2") copper washer in new compuvalve outlet port, then install adapter. Refer to Figure 33. Tighten to 34-41 Nm (25-30 lb/ft).
34. Install new small (3/8") washer in adapter, then connect compuvalve outlet line and finger tighten. Refer to Figure 33.
35. Install new larger copper washer in compuvalve inlet line port, connect new compuvalve inlet line to compuvalve and finger tighten. See Figure 33.
36. Tighten compuvalve inlet and outlet lines to 34-41 Nm (25-30 lb/ft).Also tighten compuvalve inlet line at the regulator outlet port to 34-41 Nm (25-30 lb/ft).
37. Lower vehicle.
38. Replace existing air cleaner outlet tube with production outlet tube in kit. Align indexing arrows on outlet tube and resonators.
39. Position intake air resonator assembly on top of engine, then connect Intake Air Temperature (IAT) sensor electrical connector.
40. Connect MAF sensor electrical connector.
41. Install intake air resonator assembly. Make sure throttle body O-ring is located in resonator.
42. Connect battery negative cable.
43. Calibrate VCL as follows:
^ With ignition key in Off position, disconnect connector J/P26 . Connector is located in engine compartment. See Figure 34.
^ Remove center console left side trim panel.
^ Disconnect VCL connector. See Figure 35.
^ The VCL module is attached with Velcro strips. Gently remove the VCL module down from the duct area.
^ Insert the V1-255 program card into the NGS tester.
^ Using cable K1-124 (supplied in kit), insert one end of the cable into the RS-232 and V PWR-OUT ports of the NGS tester. Refer to Figure 36.
^ Connect other end of K1-124 to the VCL. See Figure 36.
^ Turn the switch on the cable to the OFF position.
^ Insert the power cable of the NGS tester into the vehicle222s cigar lighter.
^ The NGS tester will display:
^ Using selector knob on NGS tester, select "VCL Reprogram."
^ Press the trigger button on the NGS tester.
^ The NGS tester will display:
^ Turn the switch on the cable to the On position.
^ The NGS tester will display (for 5 seconds):
^ The NGS tester will then display:
The number of bytes downloaded will also appear on the NGS screen (these numbers will reset two (2) times automatically). Calibration file downloading will take approximately 4 minutes.
^ When the calibration of the VCL is complete, the NGS screen will display:
^ Remove the power cable from the cigar lighter, disconnect cable k1-124 from the NGS tester and the VCL.
^ Affix VCL Calibration Label to VCL.
^ Position VCL in mounting slot. Align Velcro strips. Firmly press module and Velcro together.
^ Connect VCL electrical connector.
^ With ignition key in Off position, connect connector J/P26.
44. Attached to the VCL connector is another wiring harness with diagnostic connector J108 on the end.
^ Using cable N1-124, insert one end of the cable into the diagnostic connector J108. See Figure 37.
^ Insert the other end of the cable into the RS-232 port of the NGS tester.
^ Insert the power cable of the NGS tester into the vehicle222s cigar lighter.
^ Then with key On, Engine Oft (KOEO) read the NGS tester.
^ The NGS tester will display:
^ Using the selector knob on the NGS tester, select "Recalibration".
^ Press the trigger button on the NGS tester.
^ The NGS tester will display:
^ The NGS tester will display:
^ The NGS tester will display:
^ Once the calibration is complete turn the ignition key to Off position.
^ Remove the power cable from the cigar lighter.
^ Disconnect the N1-124 cable from the NGS tester and from the diagnostic connector J108.
^ Remove V1-255 program card from the NGS tester.
^ Install center console left side trim panel.
NOTE:
Make sure your SBTS machine is updated with the February 98 CD.
45. Calibrate powertrain control module by referring to SBTS for PCM calibrating procedure. Select the correct calibration code from the table as shown.
46. Start engine, verify proper vehicle operation on gasoline, by performing KOEO self test.
NOTE:
A QUALIFIED CNG SERVICE TECHNICIAN MUST BE PRESENT WHEN FILLING A CNG FUEL TANK AFTER ANY FUEL SYSTEM RELATED REPAIRS. AN ON-SITE (AT THE FILLING STATION) LEAK TEST MUST BE PERFORMED BEFORE LEAVING THE FILLING STATION. THE TECHNICIAN SHOULD BRING A BASIC TOOL SET IN CASE A LEAK IS DETECTED.
47. Drive vehicle on gasoline to a certified compressed natural gas filling station.
48. Make sure quarter turn valve is in the closed position.
49. Fill CNG fuel tank to a quarter of a tank. Use fuel level gauge on instrument panel to determine fuel tank level.
50. NOTE:
Perform the following step prior to leaving the filling station.
NOTE:
A flashlight may be necessary to properly see connections.
Leak test all CNG line connections at the fuel inlet, fuel outlet, PRD and the tank valve with Snoop or a mild soap and water solution.
^ If leak is found at the PRD:
a) Close the manual valve. Remove cap from manual valve. Using a 1/8 inch Allen wrench turn spindle clockwise until spindle seats in its bore. Refer to Figures 3 and 4.
b) Open the quarter turn valve.
c) Start and run vehicle in CNG mode until engine stalls or auto switchess to gasoline (light on GFI selector switch goes out). Accelerate engine to high idle (approximately 1500 rpm). Switchover will occur within 1 to 5 minutes.Refer to Figure 6.
d) Close the quarter turn valve.
e) Return to dealership to repair vehicle. Call 1-800-667-4275 for PRD service procedures.
^ If leak is found between the tank valve and the fuel tank:
f) There is no way to stop this leak at the filling station.Leave trunk open and safely return to the dealership. Remember that natural gas is much less flammable than ordinary gasoline.
51. If no leaks are detected, continue to fill tank with CNG until tank is full.
52. With vehicle operating on gasoline, return to the dealership to complete repairs.
53. NOTE:
The following test must be performed immediately upon returning to the dealership.
^ On vehicles that encountered leaks at the filling station. Bleed and vent CNG fuel system as outlined under "Fuel System Bleeding and Fuel Tank Venting."
^ Fix any leaks encountered at the filling station. Remember that copper washers are one-time use components, if the connection is loosened or taken apart, the copper washer must be replaced.
^ On vehicles that had a leak at the PRD during filling station leak test. Make sure the manual valve is returned to the automatic position (spindle turned fully counter clockwise).
^ Connect P120 to J120 at the tank valve solenoid. If Safety Recall 97573 has been performed, the connector ends will be taped to ribbed vent hoses. See Figure 38.
^ NOTE:
The CNG fuel tank must be completely full to perform the following steps. Turn off engine, switch selector to GFI position.
^ Open quarter turn valve in CNG system.
^ Start engine. Verify that the green GFI light remains illuminated.
^ Raise vehicle.
^ Leak test all connections from the intake manifold to the CNG tank, including all tank connections, compuvalve, regulator, filter, quarter turn valve and all fittings using Snoop or a mild soap and water solution.
^ Repair any leaks discovered. Never attempt to tighten or adjust fittings while system is under pressure. Close tank valve and bleed system to minimize system pressurization.
54. Install splash shield over compuvalve.
55. Lower vehicle.
56. Turn engine off.
57. Attach and secure ribbed hoses to tank valve isolators and bottom of PRD ribbed hose, if detached.
58. Install tank cover.
59. Test drive vehicle to verify proper vehicle operation on CNG and gasoline.
AUTHORIZED MODIFICATIONS LABEL
Prepare and attach the Authorized Modifications Label provided in the kit of parts. Write your P & A Code and date of repair as shown in Figure 39.
GFI IDENTIFICATION PLATE LABEL
Attach I.D. Label to underside of hood in location shown in Figure 40.