Where do you connect the fuel pressure gauge to check the fuel pressure on a 2001 BMW X5 4.4i? Is it the needle valve on the stainless steel tube on top of the engine leading to the fuel injectors?

German vehicles may run pressures that are higher, at least they used to. nearly every vehicle nowadays has a service port like a metal valve stem for a car's wheel. The gauge set comes with the right adapters for german cars as well. if you have fittings that match your service port, thats all you need. if they dont, then the parts store can often look them up or a tools store can offer the set very inexpensively. what is your fuel system called now? I have cis- electronic. or (K-jetronic) for Konstant. Knowing about yours is very highly recommended before testing. I would look it up or get a free book from the library.