I was driving the other day and my traction control light came on and then the engine was throttled down.  Then the engine just shut off.  i couldn't get it to start for around 10 minutes.  after the 10 minutes, it fired right up.  didn't have an issue until i got off the highway and then it did it again.  after about 5 minutes, i got it started again and was able to drive 5 or so miles.  it did it again as i was pulling into my driveway.  it is a 2007 pontiac g6 gt hard top convertible with 69,000 miles and it is automatic.  the codes that came up was p0604 and p0606.  then i cleared the codes from the scanner and the only code that was left and will not erase is the p0606.  thanks for any help in advance.