Fuel problem..502 MPI.. help!!
 

Does this make sense to you guys???
I filled my 1999 271 Fastech (502 MPI) for a weekend on Lake Powell, Utah. It ran perfect all weekend until returning to the marina. My fuel guage was reading about 1/4 tank so I thought I had at least 20 gallons left. When I opened it up on some pretty rough water, the fuel guage started to bounce to "E" and the the low fuel warning light flashed on each bounce. Each flash also corresponded with the engine cutting back. I cut the throttle and was able to idle into the marina without the engine cutting out. I added 20 more gallons of fuel. Then, the motor wouldn't start for about 1/2 an hour. Finally, it started and then ran normal. I noticed during the time it would not start, the electric fuel pump definately sounded different, so I am guessing I had air in the lines eventhough I didn't think this was possible with EFI.
Was I starving for fuel and if so, why would Formula design the fuel tank so that only 80 or so gallons are usable? Did I damage my fuel pump by running it dry? What else should I be looking for or worried about???

At least you made it with 20 gallons left, my 2000 271 runs out of gas at a half tank, go figure! I took it back to the dealer they changed the fuel sender and i still have the same problem. So now i know when it hits 1/2 time to get fuel! If you ask me a 80,000 boat should be correct with the fuel guage. That was the fuel pump sucking air. If you run out of gas turn the key on a couple of times to purge the air out, then try to start the motor. Hope this helps!

also you probably did not damage the fuel pump. And it was my third time out when i ran out of gas and had to be towed in. I wanted to kill somebody i was so mad. I really dint't think i ran out of gas, but decided to put gas in it just to see if that was it and sure enough it was!

In all of the boats I have owned, I have yet to see a fuel guage read accurately. My 382 Formula will take just over 100 gallons when the guage reads just under the full mark. I have just learn to fill at 3/4 tank.

As far as your fuel pump is concerned my buddy with 575's ran out of fuel this weekend. After filling up, the port motor started and the starboard did not. The local mechanic replaced the inline electric fuel pump and it started and ran fine.

The marine pump won't suck gas, it pushes it. If the static pressure drops, the pump will starve the engine. EFI"s are hard to restart. Increase fuel line diameter and/or eliminate 90's.

Thanks for all of the info. Whew!! What a relief!!
My main concern was understanding why I was stranded. If I know how to prevent it...at least for now....that is good peace of mind. Sounds like I just need to keep the fuel tank above 1/2 and enjoy the rest of the summer without needing a tow. I will take care of it this winter though.

Thanks again!!!!