Disconnecting the electrical harness and checking the voltage supplied to the pump revealed a healthy 12 volts - the problem was definitely with the pump.
Luckily for us, one of Pelican Parts' suppliers had a warehouse a mere two miles away, and we were able to obtain a new pump the next morning.
Carefully remove the ring from the top of the pump. Make sure that you are prepared at this stage, with a heavily ventilated garage, plenty of paper towels, and rubber gloves (we didn't have any gloves with us in Vegas).
Pull up on the pump, and the entire assembly should come right out of the tank (Figure 5).
For reference, the new pump's screen was completely white.
Remove this cover, and the thin foam seal underneath it (Figure 3). Disconnect the two connectors that mate with the pump (Figure 4).Now, disconnect the fuel lines that feed into the top of the pump.There will be some gas spillage here - have a roll of absorbent paper towels on hand.This article is one in a series that have been released in conjunction with Wayne's new book, 101 Performance Projects for Your BMW 3 Series.The book contains 272 pages of full color projects detailing everything from performance mods to timing the camshafts.We spent all night trying to figure out why the car wasn't starting, checking ignition, electrical components, etc. We pulled out the rear seat, and pulled off the fuel pump cover.Surprise - the pump was not making any noise or vibration when we tried starting the car.I had put about 500 or so miles on it since the head gasket replacement, but the gas that was sitting in the tank probably still had some old gas mixed in there.While we were tooling around in Vegas, I let the gas level get really, really low in the tank.We then set out to perform the arduous procedure of a fuel pump replacement in the parking lot of our hotel!Needless to say these weren't ideal circumstances for performing this repair, but I thought I would document what we did, as you may find yourself in a similar predicament if your fuel pump fails on you. This particular car had been sitting for an entire year, as I slowly performed a head gasket replacement on it.