1985-1996 GM Astro/Safari CMFI Assembly Repair Guide

The CMFI assembly is mounted to the lower intake manifold. The upper intake manifold assembly must be removed for access. The CMFI assembly includes a fuel meter body, gasket seal, fuel pressure regulator, fuel injector and 6 poppet nozzles with fuel tubes. Should a failure occur in any components of the CMFI unit, the entire assembly must be replaced.
1. Remove the plastic cover and properly relieve the fuel system pressure.
2. Disconnect the negative battery cable, then remove the air cleaner and air inlet duct.
3. Disengage the wiring harness from the necessary upper intake components including:
Throttle Position (TP) sensor Idle Air Control (IAC) motor Manifold Absolute Pressure (MAP) sensor Intake Manifold Tuning Valve (IMTV)
4. Disengage the throttle linkage from the upper intake manifold, then remove the ignition coil.
5. Disconnect the PCV hose at the rear of the upper intake manifold, then tag and disengage the vacuum hoses from both the front and rear of the upper intake manifold.
6. Remove the upper intake manifold bolts and studs, making sure to note or mark the location of all studs to assure proper installation. Remove the upper intake manifold from the engine.
7. Disengage the injector wiring harness connector at the CMFI assembly.
8. Remove and discard the fuel fitting clip.
9. Disconnect the fuel inlet and return tube and fitting assembly. Discard the old O-rings.
10. Squeeze the poppet nozzle locktabs together while lifting each nozzle out of the casting socket. Once all 6 nozzles are released, carefully lift the CMFI assembly out of the casting.

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