Repair the Valve Cover Diaphragm and Seal

1. Remove the engine cover to access the valve cover assembly. 2. Carefully pry off the plastic cap covering the PCV diaphragm located on top of the valve cover. 3. Remove the torn rubber diaphragm and the internal spring, cleaning any oil residue from the housing. 4. Install a new, high-quality silicone PCV diaphragm and ensure it is seated correctly with the spring. 5. Snap the plastic cap back into place, ensuring it is airtight. 6. Inspect the surrounding valve cover gasket for any secondary leaks caused by the previous pressure imbalance. 7. Clear the stored P0171 error code and verify that Short Term Fuel Trim values stabilize at idle using an OBD-II diagnostic tool.

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