[QUOTE=xsv4rce;588138] I wish it was a worn turbine would be a good excuse for that TD05-20G upgrade haha. :)[/QUOTE]

I am sure you can find some way or another to damage it, and require upgrade..

hmm have same symptoms as of last week, also 06 wrx... same mods but verso

Any change in airflow may require an ECUTek tickle...the fact that the OE filter improved things may hint at this. Also bad fuel can stuff things up...in such cases it's best to run the tank to reserve then fill up with a new batch.
I suggest you take it to MMS (I'm guessing that's where the ECUTek was done) and get Steve to check the ratios...however you will have to delay this as Steve is currently away from work on sick leave for at least a little while.

It would help if you could get a learning view shot of the ECU. You don't need to have the engine running to do this; it just takes a snap shot of a few learned parameters in the ECU. Will need a laptop, tactrix cable and learning view software from the romraider forums.

Or if you can't do that you can try to log the following parameters:

Engine Load
Engine Speed
A/F Learning #3
Knock Sum
Manifold Relative Pressure or Boost
Primary Wastegate Duty Cycle
Throttle Opening Angle

Just a note though, if you have crap fuel it will use the failsafe fuel map which is super rich and force the car to run wastegate boost, which might explain it feeling slow.

Thanks to all for the help, it is much appreciated :D. I drove the car this morning part and full throttle there is no hesistation, it got better progressively (was a little on the way to the gym, then less and less on the way and on the way back, etc).

I think it may have been a bad batch of fuel combined with the K & N filter. I did switch BP's last night but the OE filter back in made a big difference immediately (lesson 1 learned).

I am also going to get a pvc pipe or find a resonator and remove and seal the bottom and place it back in the car to go back to stock flow (lesson 2 learned).

Will have City Subaru look at the spark plugs come service time soon but for now its back to the way it was a couple days ago.

[QUOTE=riceman1991;588155]I am sure you can find some way or another to damage it, and require upgrade..[/QUOTE]

Rhys help me :)

Back to normal
 

Re-installed a resonator (thanks so much Rhys, very much appreciated).


Chopped the bottom off the resonator and cut out some thin plastic to cover the bottom, stuck plastic with black silicone and then taped over with black duct tape for a "hand-built" finish :p

Car drives like it used to (engine I shall not touch again haha).

Thanks all
-Shane.