Hello I'm new here and I just had a few questions. If you know of other threads that would have the answers that would be great. I currently own a 2000 Chevy 2dr Blazer. I replaced my fuel pump back in December with this Replacement REPG314504 Fuel Pump | Auto Parts Warehouse .
Well it decided to stop working. So Instead of dropping the tank we decided to cut a hole in the floor ( see picture ).A few issues I'm having we disconnected the 4 wires in the back. Solid Black, Black/white stripe, Purple and Grey all of those run through the truck, When we installed the new pump we also installed a new wiring harness. The colors are Purple, Grey, and 2 solid black wires. So what I'm trying to figure out is which black one connects to the black/white one? Also It's been internment on the meter, Sometimes it would read 5v or 0v and that's on the solid black wire.

I also changed the relay with a new one. Still no power, I also cleaned the ground in the back near the tank. We decided to the hook the meter to the The fuel pump prime term and it's reading 0v but I'm testing other relays and they're working.

I also gave in and picked up a Haynes Manual. Hopefully I worded all of this right so it's not to confusing. This is starting to stress me out because I need it for work. I'll try and get pictures of the wiring up as well. Thanks

 

Well in case you did not know, the pump will only prime for 2 sec when the key is switched to the run position. So maybe that is part of the issues you have been having.

Also it is highly recommended that you only buy ac delco or delphi pumps, as pretty much all of the aftermarket ones for these trucks seem to only last a couple of months.

Sorry I'm not too knowledgeable on the rest of your issues, but hopefully someone with that knowledge will chime in.