HowToRepairGuide.com: How to remove fuel injectors and o-rings on 1997 dodge caravan?

Below are directions:

3.3L and 3.8L Engines

See Figures 12, 13 and 14

Fig. 12: Remove the intake manifold mounting bolts Fig. 13: Remove the fuel rail retaining bolts Fig. 14: Remove the fuel rail assembly

The engines use a sequential Multi-Port Electronic Fuel Injection (MPI) system. The MPI system uses fuel injectors positioned in the intake manifold with the nozzle ends directly above the intake port. The fuel rail assembly must be removed to service the injectors. The system pressure is approximately 48 psi. (330 Kpa). Perform the fuel pressure release procedure before attempting to service the fuel injectors.

Properly relieve the fuel system pressure.
Disconnect the negative battery cable.
Remove the intake manifold cover.
Remove the air inlet resonator.
Disconnect the throttle cable and speed control cable (if equipped) from the throttle lever and cable bracket.
Disengage the Idle Air Control (IAC) motor and Throttle Position Sensor (TPS) electrical connectors. Tag and disconnect the vacuum hose harness from the throttle body and intake manifold.
Remove the EGR tube-to-intake manifold flange bolts.
Remove the cylinder head-to-intake plenum strut.
Disengage the electrical connector from the Manifold Absolute Pressure (MAP) sensor. Remove the engine mounted ground strap.
Place a shop towel under the fuel lines to catch any gasoline spillage. Disconnect the fuel line from the chassis tube by squeezing the retainer tabs together and pulling the quick-connect fitting off the fuel tube nipple.
Remove the Direct Ignition System (DIS) coils and alternator bracket-to-intake manifold bolt.
Remove the intake manifold mounting bolts and rotate the manifold back over the rear valve cover. Cover the the intake manifold to prevent the entrance of dirt or other foreign material.
Remove the screws from the fuel tube clamp and fuel rail retaining bolts. Spread the retainer bracket to allow fuel tube removal clearance.
Disconnect the fuel injector wiring connector from the fuel injector.
Disconnect the Camshaft Position (CMP) sensor and Engine Coolant Temperature (ECT) sensor. Remove the fuel rail.
Check the injector O-rings for damage and replace, as necessary.
Position the fuel rail/injector assembly on a work bench or other working area that allows for easy access to the fuel injectors.
Rotate the fuel injector and pull the injector out of the fuel rail. The retaining clip will stay on the fuel injector.
Inspect the fuel injector O-ring for damage and replace, if necessary. If the injector is being reinstalled, place a protective cap over the injector tip to prevent damage.
Fig. 1: Fuel injector type with retaining clip Fig. 2: Fuel injector type with locking slot retainer
1. Inspect the injector retaining clip and replace, if damaged.
2. Repeat for remaining injectors.

To install:

Before installing the injector into the fuel rail assembly, apply a light coating of clean engine oil to the O-ring on the fuel rail end of each injector. This will aid in the installation process.

Install the injector clip by sliding the open end into the top slot of the fuel injector. The edge of the reciever cup will slide into the side slots of the clip.

Install the injector top end into the reciever cap of the fuel rail. Be careful not to damage the fuel injector O-ring during installation.

Repeat for remaining injectors.

Make sure the injectors are fully seated in the fuel rail and the clips are securely in place. Make sure the injector holes in the manifold are clean.
Lubricate the injector O-rings with clean engine oil. Install the tip of each fuel injector into their ports and push the assembly into place until fully seated.
Install the fuel rail mounting bolts and tighten to 16 ft. lbs. (22 Nm).
Install the fuel tube retaining bracket screw and tighten to 35 inch lbs. (4 Nm).
Reconnect the fuel injector wiring.
Attach the electrical connectors to the CMP and ECT sensors.
Remove the covering on the lower intake manifold and clean the mounting surface.
Install the intake manifold gasket onto the lower manifold and install the upper manifold. Hand tighten the bolts only.
Install the alternator bracket-to-intake manifold bolt and cylinder head-to-intake manifold strut bolts. Do not tighten.
Tighten the manifold bolts, in sequence, to 21 ft. lbs. (28 Nm).
Tighten the alternator bracket-to-intake manifold bolt to 40 ft. lbs. (54 Nm).
Tighten the cylinder head-to-intake manifold strut bolts to 40 ft. lbs. (54 Nm).
Attach the ground strap and MAP sensor electrical connector.
Connect the vacuum harness to the intake plenum. Connect the PCV hoses.
Install a new gasket and connect the EGR tube to the intake manifold plenum. Tighten the bolts to 16 ft. lbs. (22 Nm).
Connect the electrical connector to the TPS and IAC motor. Connect the vacuum harness to the throttle body.
Install the ignition coils and tighten the retainers to 105 inch lbs. (12 Nm).
Install the fuel hose quick-connect fittings to the chassis tubes. Push the fittings onto the tubes until they click in place. Pull on the fittings to ensure complete insertion.
Install the throttle cable and speed control cable, if equipped.
Install the air inlet resonator.
Reconnect the negative battery cable.

Turn the ignition key to the ON position and access the DRB scan tool ASD Fuel System Test to pressurize the fuel system. Check the fuel system for leaks.

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