The Difference Between Fuel Sending Units & Fuel Pumpsby Richard Rowe
Fuel systems are fairly simple as a whole; a pump send fuel through the lines, which feed the carburetor or fuel injectors. However, in the midst of that simplicity lay a number of different components that make it all happen. It all starts with an understanding of some fuel system basics.
Fuel pumps come in two basic varieties: in-tank and in-line. Most fuel-injected cars use a high-pressure in-tank fuel pump that pushes fuel through the lines from inside the tank. In-line pumps sit outside the tank but near it and usually below it, and provide a low-pressure flow of fuel to keep the carburetor's reservoir full.
Fuel Sending Unit
A fuel sending unit doesn't "send fuel" as its name implies; it sends an electrical signal from the fuel level sensor to the fuel gauge. Only cars that use electronic fuel gauges or fuel injection computers utilize a fuel sending unit.
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