Old pump died and did a swap out now it still wont start.

I checked the electrical connector and I had power at the connector so I assumed it was something wrong with
the new pump I put in. So I pull it out, rest it on the ground, turn the key on and nothing still.

My dad grabs a set of alligator clips, clips one on the pump and one on the exhaust and PRESTO it works. A bad ground.

So here's the thing, were does it get it's ground? from one of the wires in the connector, or from the tank itself?
Installed the whole thing again thinkin it must ground to the tank which is somehow grounded to the frame, NOTHING.

any help?

 

Ignore my other reply..

Theres a few grounds. The main ground for the pump is in the wiring harness at the top of the pump. You should have had to cut the factory end off the wiring harness and splice in the redesigned end that comes with all GM-spec pumps, but if you got a used one you may not have had to do that.

So check that ground...other than that, theres a ground strap that mainly grounds tank itself to discharge static that goes up to the frame by the filler neck. You should be able to see those pretty clearly though from beneath the truck.

Did you check the fuel pump relay? I'm bnot positive, but if it controls power by switching ground, the relay might not be connecting ground properly, and by jumping to the exhaust, youre bypassing the relay. Worth checking..

 

Ok I didnt get any new electrical connectors, whats up with rewiring everything?
I just swapped out the pump, not the whole sending unit so why does it have to be redone?

And the static grounds out the filler neck, and cant ground the tank cause of the rubber hose between the filler
and tank (i think).

I think the relay switchs power, cause even though I had it jumped to ground it didnt start till I turned on the key and gave it power
I think maybe wrong pump or missing elec. connectors you speak of then.

 

If the connector looks good (not melted or corroded), there is really no reason to replace it.

About the ground. The fuel pump ground is in the connector to the pump, not through the tank. To be able to help with any greater detail, we really need to know what it is you are working on. It wastes our time to have to search back through your old posts to find that answer. Please update your signature (accessible via the "My Profile" link) to include this information and also check the box which attaches it to all posts (also in your profile).

 

All the new fuel pumps I saw had a 'REDISGNED GM CONNECTOR' to fix an issue with the stock ones apparently. The new pumps I saw (Airtex and Spectra Premium) both had the same connectors, neither of which were the little cube ones that are stock..just a flat-4 that has to be spliced in.

Mine wasnt corroded at all, but still had to replace the sucker

 

Ofcourse, if the pump used has a different connector, then you must change it. If the pump has the same connector, replacement is really only necessary if there is a problem with the original.