Electric Fuel Pump Module Assembly For Cadillac Deville Cadillac Eldorado V8 4.6L 1998-2002 Engine 4.6L/V8

Extended cranking, intermittent no-start, stalling, low fuel pressure, weak acceleration, an inaccurate fuel gauge, or an evaporative-system fault can indicate a tank-module problem, but power and pressure should be tested first. The BDFHYK E3974M is an in-tank fuel pump module for specified 1998–1999 Cadillac DeVille and 1998–2002 Cadillac Eldorado models with the 4.6L V8. Confirm the exact model year, flange, two electrical connectors, pressure-sensor provision, outlet layout, module depth, float arm, and OE reference.

E3974M Fuel Pump Module for Cadillac DeVille and Eldorado

Listed Applications

• 1998–1999 Cadillac DeVille 4.6L V8
• 1998–2002 Cadillac Eldorado 4.6L V8

Do not extend the DeVille application through 2002 solely because the Eldorado range continues to that year. The original module and OE number must match.

Confirm Both Electrical Connectors and Sensor Configuration

Referenced E3974M configurations use separate four-blade and three-blade electrical connections and include fuel-level sender and fuel-tank pressure-sensor functions. Compare the flange, connector count and keying, outlet, module height, reservoir, strainer, pressure sensor, float arm, and retaining method with the removed assembly.

E3974M OE and Interchange References

Common references include E3974M, 19180103, 19180104, 25322891, 25325871, 25338963, MU1789, FG0118, FG0140, P74797M, P74844M, P74977M, SP3974M, 953-5074, and 323-01152.

Cadillac Fuel-System Diagnosis Before Replacement

• Verify battery voltage and normal cranking speed.
• Check the fuel-pump fuse, relay/control circuit, power feed, and ground.
• Measure voltage and voltage drop through both module connectors.
• Measure fuel pressure and residual pressure.
• Separate pump, sender, pressure-sensor, gauge, and evaporative-system faults.
• Inspect the tank for water, sediment, rust, or deteriorated fuel.

Ignition, injector-control, security-system, crank-sensor, wiring, and engine-management faults can create similar symptoms. Complete the diagnosis before lowering the tank.

DeVille and Eldorado Installation and Final Checks

1. Relieve fuel pressure and disconnect the battery.
2. Clean the tank opening before removing the module.
3. Label both electrical connectors and record the line and float-arm orientation.
4. Inspect the pressure sensor and sealing surfaces.
5. Remove contamination and repair damaged wiring or tank conditions.
6. Install a new seal and fully secure the retaining ring.
7. Reconnect both plugs and the fuel line without forcing them.
8. Prime the system and inspect for leaks.
9. Verify pressure, starting, engine operation, gauge response, and evaporative-system integrity.

Do not run the pump dry. Incorrect connector placement or a damaged pressure-sensor circuit can create repeat faults.