First off by a can of MAF cleaner, remove the two small screws holding the MAF in the intake tube off the air filter box.
Spray the cleaner up that tube and tap it on a clean towel and see what comes out. put it back in and start the car and drive it for a few to make sure it runs ok or the same.
if there's no change, do a boost/vacuum leak check. Take a pint size paint can and plug that large hose off the air filter box with the MAF in it. Take the small hose off the blow off valve, give that hose a short quick blast of air from a compressor, put your thumb over the hose and listen for leaks. Air should come out when you remove your thumb.
These cars on a stock tune will not have much until the turbo hits boost. A tuner like www.tuningalliance.com
can make the power more progressive and more responsive.
miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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