I have a 2007 Pontiac g5, I replace the fuel pump because the connection where corroded to the fuel pump. When I first started the car worked fine and then when i turn it back again and the engine run ruff. I check with the ignition on for power to the pump and there was. When I started the car again while running ruff i check for the power to the pump and it was gone. Is this a safety switch or an electrical problems? Does the pump needs 12 volts all the time?
I would get my hands on a fuel pressure gauge and check the pressure at the fuel rail with the engine running.
correct, I all ready checked and when I had the bad burn pump because of the corroded wires. The gage would show pressure but it would jump around and now it is the same but a little bit less worse. Now I’m thinking on the re connection I did to the wire because I had to buy a new pin and of course put the wires together and use shink wrapt.
You need a steady adequate fuel pressure.
Well you could have a bad relay too or the pigtail connection or the wire itself it things heated up a little from the back connection. Usually they replace the relay and pigtail at the same time as the pump to make sure. At any rate yes it needs power all the time to run, otherwise it would just stumble while the residual pressure is used up.
I will replace the relay it does not cost too much, but what you say about the first time I started the car it worked fined ? Can relays come back to life for seconds? I do admit I was to exited and ready and happy to see my car run just fine. That I decided to re connect my amp and base speaker witch comes with a cell bactery. But I check the pin if it had burn, meaning I put down the gas tank down to verified if the pin burn again but no everything look fine. After that my car run ruff again . Oh I did found a electrical pece bolting in my gas, I took it off so at least I know I did not waste time. But still I run the car for just one minute I could not denage my pump because a second filter after the pump would of stop it .