1. Check the Simple Stuff First:
* Fuel Sender Unit: This is the most common culprit. The fuel sender unit is located in the fuel tank and sends a signal to the gauge. A faulty sender can provide inaccurate readings or no reading at all. This often requires dropping the fuel tank, which is a significant undertaking.
* Fuel Pump Relay: A bad relay can prevent the fuel pump from functioning, leading to an empty gauge reading even if the tank has fuel. Locate the fuel pump relay in your fuse box (consult your owner's manual) and try swapping it with a known good relay of the same amperage.
* Wiring: Check the wiring harness connecting the fuel sender unit to the gauge cluster. Look for broken, frayed, or corroded wires. Repair or replace any damaged wiring. A multimeter can be helpful here to check for continuity.
* Ground Connection: A poor ground connection can disrupt the electrical signal to the gauge. Clean all ground connections related to the fuel system.
* Gauge Cluster: While less common, the gauge itself could be faulty. This is harder to diagnose without specialized tools and usually requires replacement.
2. Diagnostics:
* Visual Inspection: Inspect the fuel gauge for any obvious damage or abnormalities.
* Multimeter Test: Use a multimeter to test the voltage and resistance at the fuel sender unit connector and at the gauge cluster connector. Compare your readings to the specifications in a repair manual or online forum dedicated to 1998 Dodge Durangos. This requires understanding basic multimeter operation.
* OBD-II Scanner: While the gas gauge is usually not directly monitored by the OBD-II system, an advanced scan tool *might* show related codes if there's a problem with the fuel pump circuit or other associated sensors that could indirectly affect the gauge.
3. Repair/Replacement:
* Fuel Sender Unit: This usually requires a professional mechanic due to the fuel tank removal process, which involves safety precautions for handling fuel. Replacement parts are readily available online and at auto parts stores.
* Gauge Cluster: Replacement of the gauge cluster is usually the last resort and is also best done by a professional unless you are experienced with automotive electrical systems.
Important Safety Considerations:
* Fuel Handling: When working around the fuel tank, always disconnect the negative battery terminal to prevent sparks. Ensure proper ventilation to avoid potential fire hazards from fuel fumes. Consider using a fuel pump shut-off tool to prevent fuel from flowing while working.
* Professional Help: If you're not comfortable working with automotive electrical systems or fuel systems, it's best to take your Durango to a qualified mechanic. Incorrect repairs can lead to further damage or even injury.
Finding Information:
* Repair Manuals: A Haynes or Chilton repair manual for your specific year and model of Durango will provide detailed diagrams and instructions.
* Online Forums: Search for Dodge Durango forums (e.g., on sites like DodgeForum.com). Other Durango owners may have encountered the same problem and shared their solutions.
Remember to consult a repair manual specific to your vehicle before attempting any repairs. Safety should always be your top priority.
