Considering I have tested at each point already, I'm really starting to get discouraged. Fuel pump arrives tomorrow afternoon. I'm just so nervous. I've tested the pressure at the fuel pump, at the fuel filter, at the fuel rail.

I guess I need to stop worrying until tomorrow when the pump arrives.

Yes, no need to worry.

I know you have tested everything but if the fuel pressure at the rail is not consistently at the normal pressure it is time to do the tests again and see what has been missed.

Just wondering, did you check to make sure the line from the tank to the fuel filter was on the correct fitting? I know that you said you took one line off at a time but it is still possible to connect the first line transferred to the wrong side of the new filter.

Yes, I am sure. about 99% sure.

When I was doing the fuel pressure regulator test, I accidentally pinched the wrong line and the vehicle started dying badly, so I know the correct line is on the correct feed. The middle line goes to the return tank, the outside line goes to the pump.

I assumed you were sure but I thought it good to ask.

I think you have done an great job and have shown fantastic patience tracking the cause of the problem.

You'll get there.

I would look at the alternator once you get the X running again. Could be that the 16+ volts that showed up on one of your scan could be killing all those fuel pumps, since the fuel pump was originally designed to work on 12 volts and not 16 volts which is a 33.33% increase.

I honestly don't know where that spike of 16v came from. Normally it is running somewhere between 13 volts (according to Torque).

Last time I ran INPA the voltage was not 16 volts.

:iagree: that you should watch the alternator closely when you get it running. I would think the sensitivity of voltage hiccups to BMW electronics would also be rearing its head if a spike was high enough to fry the fuel pump but who knows?

Back when I was running torque (before the stereo died) I monitored the voltage all the time (I have an amplifier and subwoofer in the rear, so I liked to check up on the voltage) never saw anthing past 14.4v

So where did the 16+ come from?

Good question. I've never seen any spikes at all before, and honestly didn't even notice it until Upallnight pointed it out.