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Fuel Relay Diagnosis in a 1994 Chevrolet 1500

by Giovanni Badalamenti

Occasionally, the 1994 Chevrolet 1500 might develop problems with its fuel relay system. Some simple diagnosis techniques can often resolve the problem. While troubleshooting, wear protective gear and keep a class B fire extinguisher nearby.

Relay Location

The fuel relay is located on the passenger side fire wall, "near the top of the compartment under the relay cover," according Haynes manuals. Mounted about 6 inches to the right of the fuel pump fuse, it's black with five wires coming out of the bottom.

Preliminary Checks

Examine fuel lines for a leak or crimped hose (or fuel line) impeding the flow of fuel to the carburetor. Have someone turn the ignition on while you listen for the fuel pump (located in the fuel tank) to activate. A whirring sound can be heard for approximately two seconds when the fuel pump is working properly. If there is no sound, turn the ignition off and remove the cover from the underhood fuse/relay center. Using the guide printed under the cover, locate the fuel pump relay fuse. Examine it for usability. Replace if the element is broken.

Primary Checks

Next, test for electrical current by performing a voltage check. If the fuses and relay are good, check the fuel pump relay control circuit from the relay to the engine control module/powertrain control module (ECM/PCM). If the circuit is good, have the ECM/PCM diagnosed and serviced by an authorized repair shop or dealership.

About the Author

Based near Orlando, Florida, Giovanni Badalamenti has been writing professionally since 2010. His articles on cooking, local restaurants, fantasy sports and attractions have appeared in various online publications. Badalamenti is currently enrolled at Seminole State College in Lake Mary, Florida, pursuing an Associate of Arts in nutrition.

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