996 TT Head Scratcher Problem

[JUS8AV8]

Hello all.

I have a 996 Turbo that’s giving me a real head scratcher of a problem. From cold start to approx. 20 minutes of operation the car runs fantastic! Develops boost very well, very responsive, no issues. However, depending on the ambient temp outside, once she gets hot (not operating temp...but approx 10 min after reaching op temp), Once at this point I can NOT apply throttle without severe hesitation. Once hot I can only slowly , I mean very very gradually apply throttle without hesitation.

Okay, before the usual items are covered I have (within the last 60 days) replaced: coils, plugs, fuel pump, venturi tubes, sending unit, FPR, MAP, N75, MAF and fuel filter. There are NO codes, and no check engine lights. Also, I have don’t countless pressure tests…no leaks.

My ONLY assumption at this point is that something, once it gets HOT, is failing. I want to be brave enough to continue to try and push it while is hesitating to force a CEL, but haven't yet. Usually i just lift and gingerly apply throttle. During this time it idles fine, with no issue. But when its time to apply throttle, no beuno.

ANY ideas on what that something could be?

Thanks in advance

[techweenie]

Is there a temp sensor that's gone non-linear? I'm at a loss.

[looneybin]

Does a turbo have an SAI?
Maybe the change over valve is sticking