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Fuel Injector: Service and Repair






Injector Removal and Installation

Removal

WARNING:
Compressed natural gas is flammable and highly explosive. You could be killed or seriously injured if leaking natural gas is ignited.
Stop the engine, and keep heat, sparks, and flames away.

1. Fuel Pressure - Relieving (Between the engine and the manual shut-off valve) (Natural Gas Model)





WARNING:
Compressed natural gas is flammable and highly explosive. You could be killed or seriously injured if leaking natural gas is ignited.
Stop the engine, and keep heat, sparks, and flames away.

This procedure should be done outside in a well-ventilated area or in a properly equipped CNG shop.

This procedure will allow you to safely work on any part of the fuel system downstream of the manual shut-off valve, such as fuel pressure regulator P1 or the fuel injectors.

1. Close the manual shut-off valve (A).

2. Start the engine, and let it idle.

3. After a few minutes, the engine will stall.

4. Turn the ignition switch to LOCK (0).

2. Wiper Arm Assembly





NOTE: Set the wiper arms to the auto-stop position before removal.

1. Remove the cowl top wiper covers (A).

2. Remove the wiper arms (B).

3. Both Side Cowl Covers





1. Remove the side cowl cover (A).

2. The left side is shown; repeat on the right side.

4. Center Cowl Cover





1. Remove the center cowl cover (A).

2. Disconnect the windshield washer tube (B).

3. If necessary, remove the hood rear seal (C).

5. Under Cowl Panel





1. Remove the under cowl panel (A).

6. Fuel Injector (Natural Gas Model)

1. Disconnect the connectors (A).






2. Remove the wire harness clips (B).

3. Remove the nut (C) and the fuel feed hose (D).

4. Remove the fuel rail mounting nuts (E) from the fuel rail (F).

5. Remove the screws (G) and the injector clips (H) from the fuel rail.

6. Remove the injectors (I).

7. Remove the injector covers (J) from the injectors.

Installation

WARNING:
Compressed natural gas is flammable and highly explosive. You could be killed or seriously injured if leaking natural gas is ignited.
Stop the engine, and keep heat, sparks, and flames away.

1. Fuel Injector (Natural Gas Model)

1. Install the injector covers (A) to the injectors.






2. Coat the new O-rings (B) with silicone oil or polyalkyleneglycol (PAG) oil, then insert the injectors (C) into the fuel rail (D).

3. Install the injector clips (E) and the screws (F).

4. Install the fuel rail and the injectors into the cylinder head (G).

5. Install the fuel rail mounting nuts (H).

6. Connect the fuel feed hose with a new O-ring (I), then install the nut (J).

7. Connect the connectors (K).

2. Manual Shut-off Valve - Open (Natural Gas Model)





1. Open the manual shut-off valve (A).

3. Fuel Supply System Leak - Inspection (Natural Gas Model)




Check for a gas leak if there is an odor coming from the vehicle. Compressed natural gas (CNG) can only be smelled, not seen.

1. Open the hood and the fuel fill door.

2. Connect a vacuum pump/gauge, 0-30 inHg, to the hose (A) from fuel pressure regulator P1, and apply 67.7 kPa (20.0 inHg, 508 mmHg) of vacuum.

3. If fuel pressure regulator P2 does not hold vacuum, replace it before continuing to the next step.

4. Inspect the fuel lines and hoses under the hood for kinks, abrasion, and other signs of damage.

5. With the manual shut-off valve open, turn the ignition switch to ON (II), but do not start the engine.

6. After the fuel pressure regulator shut-off solenoid valve/fuel tank internal solenoid valve operates for about 2 seconds, the fuel pressure in the fuel lines rises.

7. Turn the ignition switch to LOCK (0).

8. Repeat this two or three times.





9. Within 1 minute, check for any damaged lines with a leak detector (A) (Snap-on Combustible Gas Leak Detector or Snoop Liquid Leak Detector (B)).





10. If no damage was noticed during the inspection, turn the ignition switch to ON (II) for 2 seconds, then turn the ignition switch to LOCK (0).

11. Within 1 minute, check for a leak at the vent hose outlet inside the fuel pipe protector (A).

12. If you detect a leak, remove the vent hose, and check the fuel lines and fittings at the in-tank solenoid valve and the join block with a leak detector.

13. If you cannot find the leak, raise the vehicle on a lift, remove the under-floor cover.

14. Inspect all the fuel lines under the vehicle, visually, and with a leak detector.

15. If you still cannot find the leak, remove the rear seat, then check all fuel lines and fittings at the fuel tank and the fuel joint block.

4. Under Cowl Panel





1. Install the under cowl panel (A).

5. Center Cowl Cover





1. If necessary, install the hood rear seal (A).

2. Connect the windshield washer tube (B).

3. Install the center cowl cover (C).

6. Both Side Cowl Covers





1. Install the side cowl cover (A).

2. The left side is shown; repeat on the right side.

7. Wiper Arm Assembly





NOTE: Set the wiper arms to the auto-stop position before installation.

1. Install the wiper arms (A).

2. Install the cowl top wiper covers (B).
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