Engine Knocking Noise problems of the 2003 Nissan Sentra

The Nissan 2003 Sentra was bought from a private dealer in 2009 and was driven almost a year until it started consuming excessive amounts of oil. It also had a loud knocking noise when running. It was serviced twice until it was discovered there was a recall on this car by Nissan for the exact symptoms it was having. The recall states that certain engine operating conditions may cause damage to the pre-catalyst. Material from inside a damaged pre-catalyst could enter the engine and result in increased oil consumption. If the engine oil level is not checked on a periodic basis and drops below the low level engine damage may occur which could result in a fire. This is a concern since this is my son's car and I do not want him in a car that could cause him harm. I have been in contact with Nissan and they say there are no open recalls on this car and there is nothing they will do. The recall campaign was dated 7/29/2003. I have looked into this matter and many owners of Sentra's and altima's were effected by this recall and apparently the fix for the recall was a band- aid for a major defect. The recall was to reprogram the emc card the problem is the damage was already done to the engine and a new motor and pre-catalytic converter was the fix for this defect.