Honda Civic Service Manual: Internal Combustion Powertrain Control

Valve Inspection (R18A9)

1. Fuel Pressure - Relieving (Between the engine and the manual shut-off valve) (Natural Gas Model) Compressed natural gas is flammable ...

Engine Control

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See also:

Honda Civic Owners Manual. Tire Pressure Monitoring System (TPMS)
U.S. models Instead of directly measuring the pressure in each tire, the TPMS on this vehicle monitors and compares the rolling radius and rotational characteristics of each wheel and tire while you are driving to determine if one or more tires are significantly under-inflated. This will cause ...