Safety Precautions:
* Disconnect the negative battery terminal. This is crucial to prevent electrical shocks and potential fires.
* Work in a well-ventilated area. Gasoline fumes are highly flammable and can be dangerous.
* Use jack stands. Never work under a car supported only by a jack.
* Wear safety glasses and gloves.
* Have a fire extinguisher readily available.
Tools You'll Likely Need:
* Jack and jack stands
* Socket wrench set (metric)
* Ratchet and extensions
* Screwdrivers (Phillips and flathead)
* Fuel line disconnect tool (if necessary)
* Pliers
* Wire cutters/strippers (possibly)
* Shop rags or absorbent material
* Container for draining fuel (if necessary)
* New fuel level sending unit
Procedure (General Outline):
1. Prepare the Vehicle: Park the car on a level surface, engage the parking brake, and chock the wheels. Lower the car safely using a jack and jack stands.
2. Access the Fuel Tank: Locate the fuel tank. On the LHS, this usually involves accessing it from underneath the vehicle. You may need to remove some underbody panels or shields to get a clear view.
3. Disconnect the Fuel Lines: This is the most critical and potentially messy step. You'll need to disconnect the fuel supply and return lines from the fuel pump assembly. Before disconnecting anything, relieve pressure in the fuel system by running the engine until it stalls. Use a fuel line disconnect tool to avoid damaging the lines. Carefully drain any remaining fuel from the lines into a suitable container. Be extremely cautious to prevent fuel spillage.
4. Disconnect the Electrical Connector: Carefully disconnect the electrical connector from the sending unit. Note how the wires are connected for reassembly.
5. Remove the Sending Unit: This step varies depending on your specific model. The sending unit might be held in place by a retaining ring, bolts, or a combination of both. You might need to use a special tool for the retaining ring if it's present. Once the retaining mechanism is removed, carefully lift the sending unit out of the fuel tank.
6. Install the New Sending Unit: Carefully install the new fuel level sending unit, ensuring it's properly seated. Secure it with the retaining ring or bolts.
7. Reconnect Everything: Reconnect the electrical connector, fuel lines, and any underbody panels you removed. Make sure all connections are secure and no fuel is leaking.
8. Lower the Vehicle: Carefully lower the vehicle from the jack stands.
9. Test the System: Connect the negative battery terminal and start the engine. Check the fuel gauge to ensure it's functioning correctly. Monitor for fuel leaks.
Important Considerations:
* Fuel tank venting: Make sure the fuel tank vent is clear and not blocked. A blocked vent can prevent accurate fuel level readings.
* Grounding: A poor ground connection can also affect the fuel gauge reading.
Disclaimer: This is a general guideline. Consult a repair manual for detailed instructions specific to your 1994 Chrysler LHS 3.5L. If you are not comfortable performing this repair yourself, take your vehicle to a qualified mechanic. Incorrect repair can lead to significant problems, including fire.
