There is no steering pump as the Z4 uses electrically-assisted steering.
On my 54 reg, its the middle of the steering wheel.
There is no power steering fluid..........all electronic.
There is something wrong with it and you need to take it to a BMW dealer. The EPS is not something you can fix yourself.
The 2004 BMW Z4 has 24 valves.
The 2012 BMW Z4 has 16 valves.
The 2013 BMW Z4 has 16 valves.
The 2011 BMW Z4 has 24 valves.
The 2010 BMW Z4 has 24 valves.
The 2014 BMW Z4 has 16 valves.
The 2007 BMW Z4 has 24 valves.
The 2006 BMW Z4 has 24 valves.