Valve Lifter Oil Manifold Cleaning and Inspection

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2019 GMC Yukon XL, 2019 GMC Yukon, 2019 Chevrolet Tahoe, 2019 Chevrolet Suburban, and 2019 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

DO NOT allow dirt or debris to enter the oil passages of the Valve Lifter Oil Manifold (VLOM). Plug, as required.
DO NOT disassemble the electrical components from the VLOM.
DO NOT submerge the electrical components in cleaning solvent.
DO NOT use the VLOM outer gasket again. Remove the VLOM outer gasket and install a NEW VLOM outer gasket during assembly.

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DO NOT lift the VLOM (2) by the electrical lead frame (1).
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Remove the oil pressure sensor (1) from the VLOM.
Remove the VLOM plug (2).
Remove the PCV assembly (3).

WARNING:

Refer to Safety Glasses and Compressed Air Warning .

Clean the VLOM with compressed air.
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Inspect for loose electrical solenoids (1 - 4) or loose or missing bolts.
Inspect for damage to the electrical lead frame (5).
Inspect for a damaged electrical connector, for bent or corroded pins.
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Inspect for damaged VLOM inner gaskets (1 - 8). If the VLOM inner gaskets are damaged, the VLOM must be replaced as an assembly.
Inspect for a damaged VLOM outer gasket (9) or scored gasket surfaces.
Inspect for debris or restrictions within the oil passages of the VLOM. Refer to Cylinder Deactivation (Active Fuel Management) Valve Lifter Oil Manifold Diagnosis and Testing .