If you find them, fine.
I have searched and found no representative surveys with the words 'Umfrage  Loyalität Deutschtürken'.
But I found this"
"[...] Also Bilkay Öney, the speaker for migrational issues of the greens in the Berlin (state) parliamen, found Erdogans speach in the Köln-Arena pretty bad. He can't tell one day in the German media [mostly read by Germans, Martin] ask the Turks for more integration, and the next day [in front of only Turks or people with Turkish ancients, Martin] warn the Turks of too much alignment. That makes him uncredible. She estimates, that the speach in front of 16000 Turks [note, Turks is the word in the text, despite I'm sure there were quite some people without Turkish citizenship] mostly was for the partisans of his conservative AK party. This party has many partisans among Deutsch-Türken [don't know how to translate best, Martin]. Öney estimates, that more than one half are positioned nationalistic-conservative. They want to conserve their values, because they are afraid to lose their identity far from home."

There is a Turk from Turkey, who just came for phd, in the institute I work. I have never met a Turk less nationalistic than him. I have the impression, that living in Germany may make Turks more nationalistic instead of less.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers