Originally Posted by UncleSchnitty
the turbo being is issue is kind of a mute point to check since it only has 1500 miles on it and was checked twice by subaru (that being said they didnt notice that it was only putting out only 7psi after the $2,000 install and another $250 to have it double checked)
Did this turbo ever put out proper boost?
Learned A/F trim isn't indicating a big leak, you should also log the short term trim. These should be way more than ~5% range with a leak that big. Logging the trims is kind of a second order effect it won't always be obvious, but it should show something with this large a leak (if it's a leak). Leaking under boost should be rich with large negative short term trims. Leaking under vac should be lean with large positive short term trims.
I'm thinking some kind of wastegate related failure on the turbo at this point. I'd pop off the downpipe and just inspect the rear end of the turbo @ the wastegate area. Pop off the actuator (be VERY careful with that E-clip, it will shoot off who knows where if you aren't) and move the wastegate manually to see how it looks and is sealing. If nothing looks wrong, wire it shut, put the DP back on and try for 12+psi again.
Any pre-turbo exhaust leak causing this kind of loss of boost would be something you would hear (and smell), so it's not likely an exhaust leak, but still could be an exhaust restriction.