Fuel pump issue?.. car cranks but doesn’t turn over fully now.

No CEL that I know of.

• We tested the fuel pump connection and we found ground and hot and that was good..

•the female part where the fuel pump relay goes into has 12V and has continuity.

•15 AMP blue fuse is not blown.

•They brand Nais relay isn’t bad I don’t think

•I’ve replaced with the New blue relay they use for the fuel pump and still nothing.

•FUEL PUMP does not hold the 12v for long enough and starts dropping volts fast

•doesn’t prime or make noise

I’m stumped and have already dove into some forums but maybe I’m not understanding something. I may miss some info in the text but I will relay it when it comes to mind.

•could it be truly just that the fuel pump is bad? I replaced it with an unknown brand when I was in tech school from my instructor. If so I’ll go get a hitachi and go get a pick a part fuel pump and see if it’ll start with that. Any help would be appreciated!

 

Might be a dumb question but have you checked for spark?
It sounds like youre on the right track to test the connector. Seems like everything is pointing to a bad fuel pump. I think rock auto does returns if you put a new one in and still doesnt work you know?

 

No such thing as stupid. I’m the one troubleshooting and that’s a good question you asked.

I have not tested spark which could be another thing but, I have recently changed all spark plugs with brand new NGK iridium and gapped to within specs. But I don’t believe it could be that, as like you said everything is pointing to bad fuel pump as I cannot hear it at all anymore. But going back to what you said again about spark that needs to be something I need to check also soon. I will get back to you either today or Monday as the fuel pump will arrive later today or whenever.

 

There are 3 things an engine needs to run. Air, fuel and spark. Check air filter to make sure it's not clogged. Pull a coil pack and check for spark. Connect pressure gauge to fuel rail to make sure you have fuel pressure. No fuel pressure means one of two things. Bad fuel pressure regulator or bad fuel pump. From what I understand you mentioned that the fuel pump voltage drops drastically and you can't hear the fuel pump run, chances are the fuel pump motor is jammed or shorted out and you will need a new fuel pump.