A8CT

I ran my wife's car down to empty in anticipation of swapping the pump - which I might do tonight.

I'm familiar with issue of running out of gas if not installed correctly. My question is at what point on the guage do you know it's past the point of starvation?

Since I'm already below 1/2 a tank, does the mean if the car starts at all I got it right?

Or, do I need to fill it and then run it down as the real test?

Magnum8, I have a feeling you know the answer to this all too well

Bob

TwoTonic

The complication is that the "pump well" is actually way above the bottom of the tank. If there is EVER a complete void of fuel in the well it will never start since it can't get enough fuel to 'prime' the scavenge pumps.

I think the Bentley even specifies that you are supposed to put a little fuel in through the filler hole after a pump replacement since that's the only way to ensure it's got enough gas in the well to prime it. That's why the filler neck actually drains into the tank via the "well"-- to make sure there's always fuel in there.

So, the net is that you have to add fuel anyway to make sure it will start. Once you do that, all bets are kind of 'off'-- the only sure test beyond that is to cycle it down beyond half, from a basically full tank.

mAgnum8

The Bentley quotes "If the ouput line from the fuel delivery module to the suction jet pumps is not pressed down into the funnel on the adapter plate, the suction jet pumps will not work and the fuel delivery module will not seal against the adapter plate." This was my biggest fear since the installation is a blind shot in the dark process. "If the baffle housing is not fuel tight or the suction jet pumps are not working, the engine will cut off due to fuel starvation when the tank is still 1/3 to 1/4 full". So says the Bentley.
I had some fuel left in the tank when I did mine. The problem with mine, was the starvation of fuel after 7 gallons of use (due to incorrect pump installed). I figured if my car started and ran after I replaced the pump then that issue was resolved since I had less than half a tank when I performed the swap. Once the car started and ran I filled up and drove it to almost the red E line (I had a gallon of gas in the trunk just in case). There's a test that a lister posted but since our "search" engine's fuel pump is shot...I tried googleing it but couldn't find it. Sorry.

backdoc

After replacing my pump, I drove around for week with a 5 gallon Jerry can in the trunk. Drove it to well below a quarter tank. Figured I was good. That was a year ago, and no problems since.