to ask you a favor

I need to ask you a favor.

J'ai une faveur à te demander.

I wanted to ask you a favor.

Je voulais te demander un service.

— Lars and the Real Girl (2007)

I came to ask you a favor.

Je suis venu vous demander un service.

— Even the Rain (2011)

She wants to ask you a favor.

Elle veut te demander un service.

— Love Actually (2003)

A want to ask you a favor.

Je voudrais te demander un service.

— The Irony of Fate, or Enjoy Your Bath! (1976)

I've come to ask you a favor.

Je suis venu vous demander un service.

I have to ask you a favor.

Je dois te demander une faveur.

— Volver (2006)