GM 12686657 Pump Assembly, Vac

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Some models are equipped with an electric powered, auxiliary vacuum pump to provide additional vacuum to the brake booster, located in the lower left side of the engine compartment and accessible through the left side wheel well. Begin by ensuring the ignition switch is in the Off position and pump the brake pedal several times to deplete any remaining vacuum. For 2015 and earlier models and 2016 Malibu Limited models, loosen the right front wheel lug nuts, apply the parking brake, raise the front of the vehicle, support it securely on jackstands, and remove the right front wheel. Next, remove the right front inner fender splash shield, disconnect the vacuum tube from the vacuum pump by releasing the quick-connect fitting, and disconnect the electrical connector from the vacuum pump. Unscrew the fasteners and remove the vacuum pump, then install the new pump in reverse order, ensuring to tighten the fasteners to the specified torque and check for proper brake operation. For 2016 and later models (except Malibu Limited), start by removing the engine cover and the charge air cooler outlet tube, then detach the vacuum line fitting from the pump. Remove the vacuum pump bolts and detach the pump from the valve cover and cylinder head, ensuring to remove any locating dowels if they remain in the cylinder head. Clean the gasket mating surfaces, inspect the vacuum pump seal and replace it if necessary, and lubricate the seal with clean engine oil. Install the locating dowels into the vacuum pump, place a new gasket onto the pump, and ensure the drive tang engages the slot in the camshaft before installing and tightening the bolts to the specified torque. Complete the installation by reversing the removal procedure.

To remove the vacuum pump, start by turning the ignition switch to OFF and pumping the brake pedal several times to deplete any remaining vacuum. Then, remove the engine cover to access the vacuum pump located at the left front corner of the engine compartment. Disconnect the vacuum hose by releasing the quick connect filling and position the power brake booster vacuum hose to the side. Disconnect the electrical connector and, if necessary, release the wiring from the bracket. Remove the nuts and pull the pump from the engine compartment, or remove the bolts from the pump bracket if needed. Retain the rubber mounting bushings and their sleeves. To install the vacuum pump, reverse the removal steps. If the replacement pump does not include rubber mounting bushings, transfer them from the old pump. Ensure the fasteners are tightened securely and check for proper operation of the brake booster system.