I have a 2004 JDM legacy with the EJ20Y engine. I imported this car from Japan and have had no major issues.. until recently. I recall driving and the car just feeling “sluggish” from 3000-7000rpm the turbo was much quieter and it just took longer to go through the rpm’s. Then I would get in the car and the issue would be gone... this has happened at least 15+ times. Best way to describe how it feels is as if there’s a sock in the engine and it can’t breathe! I have no check engine lights (or stored/pending codes) car does not burn or leak a drop of oil and sounds very healthy, while down on power it runs great! Other than being down I’d say 30-60hp. I have checked for boost leaks, checked the vacuum lines, air filter, tried swapping the MAF sensor, resetting the ECU etc.
I’m looking for any insight or helpful information! Things I’m thinking are...
-sticky boost control solenoid?
-cats clogging? (I have noticed rotten egg smell many times after parking the car)
-JDM tune vs North American fuel/octane?
-AVCS banjo bolt screen slightly clogged m? (But no check engine lights?)
-turbo on its way out, but intermittently?
-fuel pump/regulator failure?
Please help!
Wondering if anyone has had this issue with this engine? Any information is appreciated, I love this car!