|Subject:||Oil Consumption and/or Exhaust Smoke due to Oil in the PCV System|
|Models:||2004-2007 Buick Rainier |
|2003-2011 Cadillac Escalade |
|2010-2011 Chevrolet Camaro |
|2003-2007 Chevrolet Corvette |
|2009-2011 Chevrolet Colorado |
|2003-2011 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe |
|2003-2009 Chevrolet Trailblazer |
|2003-2011 GMC Savana, Sierra, Yukon |
|Built with any of the following V8 Engine RPO Codes:|
|5.3L - L33, L59, LC9*, LH6*, LH8, LH9, LM7, LMF, LMG**, LY5**|
|6.0L - L76*, L77, L96, LFA*, LQ4, LQ9, LS2, LY6, LZ1|
|6.2L - L92*, L94, L99, L9H|
|*For 2007-2009 Full Size Trucks or 2008-2009 Pontiac G8 with Engine RPO Code LC9, LH6, L76, L92, or LFA: Follow the latest version of 10-06-01-008 and re-evaluate the oil consumption. If the concern reoccurs and/or if excessive oil is found in the intake manifold as described below, also follow the PI suggestions below. Bulletin 10-06-01-008 does not apply to the Envoy, Rainier, Saab 97x, or Trail Blazer Models with Engine RPO Code LH6 because they have a different design oil pan and AFM pressure relief system.|
|**For 2007-2011 Full Size Trucks with Engine RPO Code LMG or LY5: Follow the latest version of PIP4918 and re-evaluate the oil consumption. If the concern reoccurs and/or if excessive oil is found in the intake manifold as described below, also follow the PI suggestions below.|
|Notice: Passenger Cars with Engine RPOs LS3, LS7, LS9, and LSA are excluded from this PI because they have the PCV baffle built into the intake valley cover, rather than the valve cover so excessive lifter flow does not affect them in the same manner.|
This PI was superseded to remove all passenger cars equipped with the LS4. Please discard PIP4492Y.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
On rare occasions, some customers may complain of excessive oil consumption and/or blue exhaust smoke.
Upon inspection, excessive oil will be found in the intake manifold and/or PCV vacuum tube if this PI applies.
If excessive oil consumption (greater than 1 quart of oil every 2,000 miles / 3,000 km) is verified but SI diagnosis does not isolate the cause of it, inspect the PCV vacuum pipe to see if obvious oil drips out of it and/or look through the throttle body opening to see if there is excessive standing oil in the bottom of the intake manifold (as much as a ¼ quart in many cases - a teaspoon or two is typically just normal oil residue).
If excessive oil is present, replace the driver side valve cover with the updated valve cover described below and perform another oil consumption test. These valve covers contain an updated baffle to prevent oil ingestion through the PCV system that can occur if there is an over-aggressive lifter(s).
2008 and earlier vehicles: Replace the driver side valve cover using the part number that is listed in the parts catalog. As of 6/2011, all old GM CCA/SPO stock should be purged of the 1st design valve cover so all remaining stock should be 2nd design valve covers as shown in the photo below. As a result, it is suggested to order this valve cover from GM CCA/SPO rather than a local supplier or another dealer who may only stock the 1st design valve cover. Before installing the valve cover, ensure that the PCV baffle looks similar to the 2nd design valve cover below.
2009-2011 vehicles: Replace the driver side valve cover with part number 12642655.
At this time, the latest version of 10-06-01-008 also lists this updated valve for the 2009 Full Size Trucks and 2009 Pontiac G8 with Engine RPO Codes LC9, LH6, L76, L92, or LFA but it does not include all of the additional engine RPOs and Model Years described above. This bulletin is currently under review and may be updated in the future to include additional engine RPOs and Model Years.
If blue exhaust smoke is present, also drain/clean the oil out of the intake manifold and install the intake with new intake gaskets before releasing the vehicle to the customer. If this is not performed, the customer may return with an exhaust smoke complaint due to the residual oil in the intake manifold even though their oil consumption complaint has been repaired.