PIP4977B

Bulletin No.: PIP4977B
Date: Oct-2016
Subject:
Diagnostic Tip - Information Regarding Oil Flow And The Oil Restrictor Orifice In The Engine Block Deck
Models:
2009-2011 Chevrolet Aveo
2009-2010 Pontiac Wave/G3
2008-2009 Saturn Astra
Equipped with 1.6L 4 cyl engine (RPO LXV) or 1.8L 4 cyl engine (RPO's 2H0)
This PI was superseded to update recommended field and model years. Please discard PIP4977A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
While performing mechanical engine repairs, some technicians may find a melted plastic piece in the engine block deck. If these engines are severely
overheated, the high temperature plastic oil feed restrictor orifice in the block deck may melt or distort.
The orifice is located on the exhaust side of the block, between cylinders 2 and 3, and is pictured in the first photo below. The second image below shows how
oil is directed through the block, orifice, and cylinder head passages.
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Recommendation/Instructions
If a melted or distorted oil feed restrictor orifice is found, engine replacement is required at this time.
If it becomes necessary to replace the restrictor orifice, not related to excessive engine temperature damage, please use the latest part number listed in the
parts catalog.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the
remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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