I know this is a Legacy GT. But very similar engines.
Hey guys. I've had my 2006 Legacy GT w/ 5MT for a year now... 170,000 miles on it. Still runs like a champ. Zero issues (just screwed my self) except for this "issue". I'll start with my mods first....
Grimmspeed Downpipe (catted)
Straight pipe (mufflers and resonator replaced with pipe)
Cobb Intake + box
Infamous Performance Turbo Oil Feed Line
Access port V3 w/ Cobb's OTS Stage 2 +SF 93 Octane Map
SouthBend Stage 3 clutch w/ WRX flywheel.
On to the issue.
I noticed one day (several weeks after I did the mufflers and resonator) that I started to get some readings on my knock feedback. Ever since then I've been getting reading every now and then. Some higher. I see it taking off from a stop (nothing remotely hard) to a short WOT pull on the highway. It happens often and can almost replicate anytime I want.
Thinks I have done to troubleshoot.
Different gas stations (maybe bad fuel)
Used the 91 Octane map with -5 timing set on adjustments
Tried using octane booster to see if that would help at all... Nothing..
I've reset the ecu several times
Everything I've done doesn't change anything... I'm hoping its nothing mechanically wrong with the engine..
I have a couple datalogs one from a stop and the other at WOT. Please let me know if you want something removed and added. Thanks in advanced.