A friend of mine has an 04 WRX sedan. Purchased with 1700 miles on it with about 5000 on it now, and has an HKS downpipe with a tanabe racing medallion cat back. It has a CEL on it from the downpipe, which is normal without a resistor on it to eliminate it. However, it keeps dying on the freeway after about 5 miles of driving it! He looses all power to the brakes, steering , etc. Lets it coast, turns it off and takes keys out, and then its okay. What could cause this? Also, something i noticed is that it only makes .6 bar through everygear all the time. The dealership "tempted" him with a reflash for the ECU, at his own cost of $650. Wouldn't they have to honor that it should be making full boost?