**UPDATED**

OK, so the accessport is out of the picture. I uninstalled and I am having the same power loss issues. I also placed the restrictor pill back in the line, so the problem is not accessport related.

Here is what is going on with my car:
My car is under boosting. I just did about 6 pulls (on a warm motor), and on the first 4 the boost spiked to 17/18 and dropped instantly to 15 until redline. The next few spiked to 16/17 and then instantly dropped to 13. This seems consistent with the way my car usually feels. There is more power (still not stock levels, but more) the first few pulls I make and, then the car gets slower. Also, the problem seems like it has been slowly getting worse over time. My car feels slower then my old stock wrx.

Also boost leak tested, but no leaks. Car is stock.

Please give me some advice on what steps to take. I plan on checking the bcs and feeling the turbo for play because those are the easiest things to check, but I just got the car and am not very knowledgeable yet.

 

updated, someone please give me some ideas!