What could be causing underboost code?

Since flashing the Trifecta tune I get a stored code for P0299 Turbo/Supercharge underboost code. When I told Vince about it, he responded with

It’s possible there’s a leak somewhere, but I don’t think so – or if there is, it’s a small leak. You’re seeing a turbo pressure ratio of about 2.4 (220kPa pressure / 90 BARO = 2.444 pressure ratio), which is a little on the low side for the stock turbo (they usually make closer to max of 2.5 or 2.6 but I’ve seen a few that are in this range).

So what could be causing this issue? When I first got the car, probably about 1200 miles, I got an engine light and I called OnStar and they said it was a leak in the intake ducting. The dealership said they fixed it by tightening up everything.

I don't see any CEL, only when I run the code scanner with EZFlash do I see the stored code. What could be my issue? I'm assuming I should check all clamps and make sure there isn't a hole somewhere. But what else should I check? When I ran the stock tune I didn't get the code.

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What could be causing underboost code?

What could be causing underboost code?

chevyboy695

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