On October 19, 2007, the Office Of Defects Investigation (ODI) opened a preliminary evaluation to investigate alleged stuck throttle incidents due to ice formation within the engine air intake tract in certain model year (MY) 2004-2005 Chevrolet Aveo vehicles manufactured for sale or lease in the United States.this investigation was prompted by a safety recall campaign (05F-069) conducted by General Motors Corp. (GM) involving substantially similar vehicles manufactured for sale or lease in Canada.at that time, GM issued a technical service bulletin (tsb #05-06-04-065) to address the alleged defect condition in U.S. vehicles.GM subsequently revised the Canadian recall campaign to include more detailed instructions after it discovered certain vehicles were not properly serviced under the original recall campaign.GM revised the Canadian recall campaign a second time to include more substantial changes to the throttle body, intake manifold, positive crankcase ventilation (PCV) and engine cooling systems to further reduce the likelihood of icing within the engine air intake tract.again, GM issued a technical service bulletin (tsb #08-06-04-009) to address the alleged defect condition in U.S. vehicles using the revised procedure.ODI is aware of 28 non-duplicative complaints/field reports and 46 warranty claims related to the alleged defect affecting 63 unique subject vehicles.the alleged defect condition is most likely to occur during the winter months when ambient temperatures are below freezing.however, the information provided in GM's response to ODI's information request letter dated November 2, 2007, does not capture events that may have occurred during the most recent winter months.accordingly, this investigation has been upgraded to an engineering analysis (EA08-005) to further study the frequency of the alleged defect.
