Possible fuel pump issue?
 

hi guys,
i posted an issue on my build thread but wanted to get more opinions so am posting it here as well...

tried to take advantage of the nice weather here in GA and go out for a drive in the widebody. unfortunately ran into an issue. the car stumbles upon acceleration..initially i thought maybe my fuel gauge was off and i may possibly be running out of gas (showed 3/8) so i filled her up and still the same issue. then i thought maybe it was improper venting...swooshing sound when opening gas cap which i had before as well, was only 68 degrees out, also tested by driving w/o the gas cap but same issue still. the only thing i can think of now is a bad fuel pump (bought from a forum member here). the only thing that's changed in the fuel system other than the pump is the power wire which now runs directly from a dedicated fuse via a relay. anyone have any other ideas? i've sent a pm to the seller of the pump to confirm that it was indeed a pump for the GSL-SE (i had to empty inbox) so am waiting on a response.

Check your pump inlet screen filter (in-line), located on the fuel pump itself. If that is clogged, my guess is you will need to drop and clean your tank. May need to clean your injectors also.

I keep reading about this cone filter, it's on the pump as in between the barb fitting and the pump or right before the fitting? I didn't see any cone filter on the hose when I removed the old pump and installed the other pump.

May not be there anymore if the original pump has been replaced. It is a tiny plastic screen that fits into the fuel pump inlet side. The rubber tube with a 90 degree bend in it fits over top of the filter as you install it on the pump. Do the pressure and volume test to see if fuel flow is the problem.

Just did a quick volume test from the engine bay. Got about ~2 cups of gas in a minute. So now need to lift the rear of the car and test the pump itself...that way I can determine if it's the pump or an issue before it (pre-pump filter/tank).

was able to do some more testing yesterday. i ruled out the fuel filter by doing a volume test directly from the outlet of the fuel pump. then i tested the pump itself by having the inlet pulling from an external gas tank. all tests had the same results, only able to pump about 2 cups in a minute.

also made sure my battery and wiring were fine, both registered 11.7 volts (engine not running).

so this points me to a faulty pump, right?

Battery is low at 11.7 but should run a pump ok I suppose. Looks like a pump issue to me.

yes a little low but should not hinder the flow that significantly...now if it was showing 5v or something, i might understand. plus, this is at 0 psi so a walbro 190 (which seller confirmed) should flow a little under a gallon in a minute.

am putting an order for a new pump and filter now from rockauto.

ordered a brand new Walbro 190lph pump (model GSL931). also ordered a pre-pump fuel filter from Welcome to RobbMc Performance Products will need to head to the hardware store to find the right fittings for the filter (looks like i'll need 3/8" NPT to 1/2" Barb).