2004 STI bought new just turned 60K. Have kept totally stock. Just got a CEL (cruise flashing), only symptom is maybe a little recent rougher idol.
Took it in to the dealer immediately.
Diagonstic was #2 cylinder misfiring.
They ruled out the plug, "must be compression or fuel delivery".
Checked compression in #2 = LOW (holy crap).
Checked compression in all = MARGINAL at best.
Looked in all cylinders with scope and all "beautiful".
Decided to do 60K tune (I did not do 30K tune) and replace the #2 fuel injector).
Dealer says will have to go into the engine to further diagnosis.
Car runs great, strong under acceleratoin, has never been raced or abused, religious with oil changes (Mobil 1 at every 3k) and does not burn any. In my opinion there should be no reason for significant loss of compression based on the way this car has been maintained or driven.
Any comments would be greatly appreciated.