Common Symptoms
- Engine cranks but does not start
- Engine stalls intermittently while driving
- Loss of power under acceleration
- Hard starting or extended cranking time
- Check Engine Light illuminated
- Fuel pump runs continuously or not at all
Most Likely Root Causes
- Faulty fuel pump relay
- Damaged fuel pump wiring harness or connector
- Failed fuel pump driver module or control circuit
- Corroded or loose electrical connections at fuel pump
- Faulty powertrain control module
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Component Location
The fuel pump relay and driver module are typically located in the underhood fuse/relay box or near the fuel tank on the frame rail.
Manufacturer Notes
Some manufacturers use a dedicated fuel pump control module separate from the PCM that commonly fails on high-mileage vehicles.
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