GM 88965441
Fuel Gauge Sending Unit

It is necessary to begin Fuel Level Sensor replacement in the rear tank by removing the tank then disconnecting the evaporative emission (EVAP) lines from the Fuel Tank module. Using the Fuel Level Sensor lock ring wrench (J 45722) together with a long breaker-bar will help unlock the Fuel Level Sensor lock ring without damaging it because of the j 45722 alone. Manipulate the Fuel Level Sensor away from fuel pipes to avoid injuring the joints and discard impact tools since releasing the lock ring needs significant force while hammer and screwdriver methods should be avoided. You must first secure the Fuel Tank from rotation before taking out the j 45722 tool and its lock ring. You should elevate the Fuel Tank module carefully to expose quick connect fittings under the cover. Then remove the module by disconnecting vapor line quick connect connectors from below. Set the old Fuel Tank module seal aside while placing the lock ring onto a flat surface for measuring its clearance with seven points using a feeler gauge. Relying on the "do not reuse" stamp on the lock ring can be valid for reuse when it is neither damaged nor warped but visual inspection determines the absence of both characteristics. The lock ring needs replacement when warpage extends beyond 0.41 mm (0.016 in). To install the Fuel Tank module you should first position its new seal onto the Fuel Tank then partially insert the module while quickly connecting the vapor line fittings before completing the installation. You should position the lock ring and then use the Fuel Level Sensor lock ring wrench (J 45722) tool to rotate it clockwise until locking position while ensuring correct side exposure points up and restriction to clockwise rotation only. Through the final step of processing, install the Fuel Tank while joining its evap lines to the Fuel Tank module.

The front Fuel Tank replacement must begin with front Fuel Tank removal followed by disconnecting the fuel and evaporative emission (EVAP) lines from the Fuel Tank module. The Fuel Level Sensor lock ring wrench (J 45722) allows the counterclockwise rotation of the lock ring until it unlocks but must avoid touching the module pipes. After using the tool to remove the lock ring you should lift the Fuel Tank module up to reach the quick connect fitting below the module cover before unconnecting the vapor line quick connect fitting for module removal. Replace the old Fuel Tank module seal by inserting a new one onto the Fuel Tank structure. Position the Fuel Tank module within the Fuel Tank then conduct the quick connect fitting operation on the vapor line before installing the module into the Fuel Tank. Insert the lock ring correctly then secure it with a Fuel Level Sensor lock ring wrench (J 45722) while applying clockwise rotation until reaching the lock point. Be sure the tool stays away from the module pipes during this process. The final step requires both fuel and evap lines installation on the Fuel Tank module before reinstalling the front Fuel Tank.

Always replace the fuel sender seal during installation and avoid applying any lubrication in the seal groove.

Begin by installing the new fuel level sensor.