Hello and welcome. Unfortunately, you have posted in the wrong forum. This section is for the e89 Z4 built from 2009 and still in production.
Your 2007 Z4 is an entirely different car. We can't help you our car has a very different and brand new engine. As a wild guess, have you ever changed the spark plugs??
Wild guesses are nearly useless though. Best to do a proper diagnosis. Fault code is only a first step.
The models and equipment (standard and optional) illustrated in this post reflect my misunderstanding of vehicles supplied by BMW AG to the German market. In other EU member states, the truthyness of my posts may vary. Please ignore this post. Subject to change.
Last edited by Andrew*Debbie; 06-03-2012 at 12:37 AM.