Removal & Installation (Contour & F150 - CNG)

WARNING: This page is about a different variant/trim than selected.

Raise and support vehicle. Close the quarter turn valve. Partially lower vehicle. Start and run engine with ALT/GAS switch in ALT position until engine stalls or automatically switches to GAS mode. Disconnect negative battery cable. Raise vehicle again. Remove 3 screws retaining compuvalve shield and remove shield. Slowly crack open low-pressure fittings and allow gas to vent.

NOTE: Do not discard the electrical connectors attaching hardware.

Disconnect low-pressure fittings, remove and discard washers. Disconnect vacuum line from Manifold Absolute Pressure (MAP) sensor "T". Disconnect 3 electrical connectors. Remove 2 screws retaining electrical connector and disconnect electrical connector. Remove 4 nuts and washers and remove compuvalve.

NOTE: Never reuse copper washers in low pressure fittings, always use NEW ones. Replace MAP sensor vacuum line elbow with a NEW assembly and install dry. DO NOT use electrical connector retaining screws to seat connector into position. Screws are for retention only.

To install, reverse the removal procedure. Coat outside of connector with a standard dielectric grease. Press ends and center of connector fully into the compuvalve. Install attaching hardware and screws and connect electrical connector to compuvalve. Perform LEAK TEST (CNG) under FUEL SYSTEM (NATURAL GAS VEHICLES) in SYSTEM & COMPONENT TESTING - EEC-V (BI-FUEL & NATURAL GAS) article.