GHut

I had a used engine put into my 2003 A4 Quattro that has a warranty. There is an issue with one of the turbos due to the wastegate (I think the sensor is messed up) so it accelerates slower than normal from a red light and picks up in spurts. Should that turbo be covered under the warranty? They keep telling me it's not a big deal, just that it will only effect that weird acceleration. If the turbo is part of the engine which they installed, I want to hold them accountable. Any thoughts?