I have a 2004 normally aspirated 215 HP coupe with a 6 speed manual trans. About 80% of the time the car runs fine. The other 20% it feels like the engine is in a" limp mode" - very sluggish and no power or acceleration. This started when the car had about 8,500 miles on it and has gotten progressively worse (car has about 18,000 miles on it now). I have taken it back to two different dealers at least 3 times. Cost me $100 just for the diagnosis each time I take it in. Since it never sets a code, they can't find the problem - or claim there isn't one. There seems to be no set of particular conditions that cause it - although it never happens on first start up, so it could be heat related?? Anyone else out there having the same problem?? Solutions? Any help would be appreciated.