2009 HHR 2.2 lt flex fuel
which wire in the wiring harness that runs under the passenger side back seat is the fuel pump + - I think + is the larger gray and the black is - I think not sure. And I belive ive got a gounding problem to the pump checked ground under passenger side tail light it's clean so I recleaned it tried jumping a ground and worked sometimes but not all the time can you please help. (can I ohm the winding though the relay and what should that read) works sometimes and sometimes don't weather I jump the ground or hook the ground naturally

 

Did you already check fuel pressure? That is where I usually start.

 

No but when the pump decides to work it works great so the fuel pressure I think isn't the problem I think it's in the wiring harness under the back seat on the passenger side because there are breaks the the wire and I redone them but it don't always come on when you tires the key. You have to wiggles wires and that's why I ask if anyone know which color the + and - for the fuel pump and now the the trail lights to please (I tried to ohm it though what I thought was the + and - ) what should it ohm out to please and thank you for your help

 

Power to the pump is gray the ground is under the right tail light. Power comes from relay #19 fuse #13 under hood fuse box.

Ground for the relay is on the driver side strut tower.

It's a motor, so resistance is futile (couldn't resist) any resistance is better than none.

 

Could be the intank pump starting to fail. Or loose connection under the HHR above the rear axle beam .

 

Thank you

 

That's what I was thinking when I applied 12 volt battery power to the wire no sound from fuel pump (gray wire +) and so could be bad ground and I haven't check the strut tower ground wire yet but will I get today thank you

 

If you applied 12V to the grey wire and nothing happens the relay is not your problem. Either the pump is bad or the ground is.

 

Along with the gray wire which is ground that run in the harness so in jump it with out droping the tank please and thank you

 

Thought gray was the power wire ? Not the ground.
Plus. That sentence above is impossible to understand. You should rewrite it.