Check Engine Light On problems of the 2005 SAAB 9-3

This is the sixth failure on the engine. My wife was in maryland when the check engine light came on (this is not the 1st time). The vehicle was towed an hour away in baltimore. The throttle body failed, it was repaired and then she had to get her own ride to the dealer (we are from ohio). This started happening after the engine was using a tremendous amount of oil. There was a recall because the factory aligned all the ring gaps in the same direction. After the engine was torn down and repaired the check engine light kicks on every 400 to 1000 miles. They have replaced the rings, computer, throttle body twice, air box and other smaller items. By the way each time this happens the engine goes into limp mode and doesn't go above thirty miles an hour. This is real safe at highway speeds.