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As most of you have probably gathered from past posts of mine, my car is only holding 15psi of boost in all gears in WOT. After some VAG logging I discovered that my MAF was shot, so I have ordered a new one after cleaning it failed to remedy the problem.
However, I am beginning to think that it may be my diverter valve that is the problem. It most likely needs adjusting but I'm not sure how to do it correctly to handle 21psi of constant boost.
The main reason I feel my diverter valve is faulty is because of a soft fluttering sound I can hear from the engine bay. It occurs when I lift off of the gas pedal around 3000-4000rpms while slowly accelerating. It may happen at higher RPM levels too after lifting off the gas but my exhaust drones the fluttering sound out at that point. It happens for a split second then goes away until I slowly accelerate and lift off the gas again around 3000 RPMS.
Could this be a problem with my DV and if it is, can I fix it without having to buy a new one?

Audi2ptzero

Also check all the vac lines while your at it.

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I'm positive it is in the right way because a forge DV wouldnt hold 15psi installed backwards would it?

Audi2ptzero

but you should be making 20-23 psi. Is this the forge valve that has the rubber parts in it or a piston? THe one with the rubber parts like a bosch valve should have the boost going in thru the side tube, while a metal piston valve will have the boost going in thru the bottom tube. If you put the rubber type in backwards you will tear the rubber seal since there is too much pressure being put on it on both sides.