Boost leak diagnosis via datalog?

MacheteJames

Greenie N00B Member
Car feels like it's running fine, yet I swear I hear what sounds like the "woooshhh" that's characteristic of a boost leak. The attached datalog appears to show that things are in order as well (MAF G/S feels a little low for a car given tune and mods, but I'm hitting 21psi - it's been humid, so maybe that's the culprit), so I'm at a loss to explain it except that it's either all in my head, or is actually an exhaust leak. Welcome any thoughts folks have. I did recently replace my MAF o-ring, as it was frayed, but that's pre-turbo so am not thinking it has any involvement here. Next step is a boost leak tester.

Btw, this is for a 2012, 118k, mostly bolted/tuned with the exception of a DP. Original k04, original owner.
 

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Check the tightness of the turbo to manifold bolts. I had a loose turbo/manifold connection and car felt fine possibly a bit down on power, but under boost it would give off a loud hissing sound.
Also look for soot marks indicating a leak where the exhaust manifold meets the head.
 
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