Re: '00 929 idle questions
The fuel pressure reg is easy to check. Lift the tank, locate the fpr. On mine, it's just under the rear of the tank. Pull the small vacuum line. Is there any sign of gas? It should be bone dry. If it is, now turn the ignition on to get the pump to prime. Let it pressure up, how about now, any gas dripping?
Typically, that little vacuum line runs from your fpr to one of the throttle body throats. If the diaphram fails in the fpr, then gas will leak to the throttlebody, giving you rough idle, or stall. I've replaced a couple of these now, really easy.
If you need a SvcManual, I'll get you the link.
Edit: Confirm your fpr before moving on to the throttlebodies. Recently a guy on another forum went to all the work of removing the throttlebidies, sending them in, reinstalling them, only to discover it was the fpr all along.