Welcome to the wonderful world of forced induction (FI) for performance. These type of problem are not that uncommon on performance turbo engines
THERE IS NO SUCH THING A SOMETHING FOR NOTHING
Flaws and faulty parts break faster under the stress of FI. Increase the boost and you increase the stress. If you are going to mod a car with forced induction (either add FI or increase the boost) you need to know your warranty rights.
A warranty is a form of insurance and there are federal and state laws that regulate warranties.
A dealer can not void your warranty because you modded your car. They can deny your warranty claim for a specific issue , if your modification caused the problem in question. In the case of the problem described in this post, there is a pattern of failure outside of the modification. The dealer would be legally obligated to honor the warranty.
If you are going to tune, know your rightS. Attach is the SEMA page on handle warranty issues.
http://www.semasan.com/main/main.aspx?id=60128
Most of the time you just have to say I know my right under the
Magnusson Moss Warranty act and the case law and the dealer will back off and do what is right