Fuel and Air Intake
Carburetion refers to the use of a carburetor as a means of controlling an engine's air/fuel ratio. Carburetors were used on most cars through the mid-1980s, when carmakers began a large-scale changeover to fuel injection. A carburetor holds fuel in a small reservoir called a float bowl. This reservoir is connected to a passageway leading to a venturi, a device that uses pressure differential to help meter fuel into the engine. Conventionally referred to as "barrels", it refers to the number of venturis in the carburetor. A one-barrel carburetor has one venturi; a two-barrel carburetor has two venturis, and so on, up to four venturis. Around 1980, carmakers began to add mixture control solenoids and other electronic devices to carburetors, to make them more effective by allowing additional control through an electronic engine control system.
The carburetor mixes fuel with air in the right ratios for all engine-operating conditions.
Replace the fuel filter once a year. If your car demonstrates a loss of performance or fuel economy, have the engine performance evaluated by a good shop with qualified technicians. The carburetor's health will also be checked out at this time. Other symptoms of carburetor problems include hard starting, stalling, hesitation, rough idle, black smoke from the tailpipe, or failing an emissions test. If you experience any of these problems, have them checked out at once to avoid more costly repairs.