1. Check the Obvious:
* Loose Gas Cap: A loose or improperly sealed gas cap can interfere with the fuel tank's pressure and cause inaccurate readings. Tighten the gas cap securely and see if the gauge moves. This is the easiest and cheapest fix.
* Debris in the Tank: Sometimes, debris can accumulate and interfere with the float in the fuel sending unit. This is unlikely to cause a completely stuck gauge, but worth considering if the gauge is erratic rather than completely stuck.
2. Check the Sending Unit (More Involved):
* Access the Sending Unit: The fuel sending unit is located inside the fuel tank. Accessing it requires dropping the fuel tank, which is a significant undertaking. This should only be attempted by someone experienced with automotive repair and with appropriate safety precautions (including disconnecting the battery and working in a well-ventilated area).
* Inspect the Float: Once the tank is dropped and the sending unit is removed, check the float for damage or debris preventing it from moving freely. The float is a small component that rises and falls with the fuel level, activating the gauge. A broken or stuck float is a common cause.
* Inspect the Resistance: The sending unit is a variable resistor. With a multimeter, you can test the resistance of the unit at different fuel levels (simulated by manually moving the float). This requires a wiring diagram to identify the correct wires. A faulty sending unit will usually show incorrect resistance values.
3. Check the Gauge and Wiring (Less Likely, but Possible):
* Wiring Issues: A break or short in the wiring between the sending unit and the gauge itself could cause a stuck needle. This requires carefully checking all connections and wiring.
* Gauge Failure: In rare cases, the gauge itself may be faulty and need replacing. Testing this usually requires a known good sending unit and a process of elimination.
4. Professional Help:
If you're not comfortable with any of these steps, taking your car to a qualified mechanic is the best option. They have the tools, knowledge, and experience to properly diagnose and repair the problem safely.
Safety First:
* Always disconnect the negative battery terminal before working near fuel lines or the fuel tank.
* Work in a well-ventilated area to avoid exposure to fuel fumes.
* Avoid sparks or open flames near the fuel tank.
Remember to consult a repair manual specific to your 1987 Chevy Celebrity for detailed diagrams and instructions. A Haynes or Chilton manual can be a valuable resource.
