Hi, had a strange issue the other day in our 2005 Cayenne Turbo.

When accelerating, it felt like this turbo boost was dropping off with a pewwwwwww sound then it reengaged. At one point when I tried to accelerate, it felt as if I lost a cylinder until I let off the gas and then reapplied. Once the car was warm and since then I have not had the issue. in the ECu engine codes I have this: p1681 overrun recirculating in valve output stage - No signal/communication, test conditions are not compete, fault is currently active.

I cannot find anything about this online. Anyone had experience with this? Could it be a stuck or failing BOV/Diverted valve?

Any help would be appreciated.

-D