Fuel Injector: Service and Repair

MPFI Injector Assembly:

Fuel Injector Part Number Location:

Injector Installation:

REMOVE
- Disconnect negative battery terminal.
- Relieve fuel system pressure. Refer to Fuel System Service and Repair Service and Repair
- Intake manifold plenum.

NOTICE: Use care in removing injectors to prevent damage to the electrical connector pins on the injector, and the nozzle. The fuel injector is serviced as a complete assembly only. Since it is an electrical component, do not be immerse it in cleaner.

- Fuel rail assembly.

DISASSEMBLE
- Injector retainer clip.
- Discard retainer clip.
- MPFI injector assembly.
- Injector O-ring seals from both ends of injector and discard.

CAUTION: Each injector is calibrated for a specific flow rate. When replacing fuel injectors, order replacements with the identical part number as the old injectors.

ASSEMBLE
- Lubricate new injector O-ring seals with engine oil, and install on injector assembly.
- New injector retainer clips on injector assembly.
- Position open end of clip facing injector electrical connector.
- MPFI injector assembly into fuel rail injector socket with electrical connectors facing outward.
- Push in far enough to engage retainer clip with machined slots on rail socket.

INSTALL
- Fuel rail assembly.

NOTE: Test injector seals now.
- Temporarily connect negative battery terminal.
- Turn ignition switch to the "ON" position for two seconds, then turn to the "OFF" position for ten seconds. Again turn to the "ON" position and check for fuel leaks.
- Disconnect negative battery terminal.

- Intake manifold plenum.

- Tighten fuel filler cap.

- Negative battery terminal.

IDLE LEARN PROCEDURE
Any time the battery is disconnected, the programmed position of the Idle Air Control (IAC) valve pintle is lost, and replaced with a "default" value. To return the IAC valve pintle to the correct position, perform the following procedure:

- Restore battery power.
- Connect Tech I "Scan" tool.
- Select "IAC SYSTEM," then select "IDLE LEARN" in the "MISC TEST" mode.
- Proceed with idle learn as directed.

This procedure allows the Electronic Control Module (ECM) memory to be updated with the correct IAC valve pintle position, for the vehicle, and provide a stable idle speed