I have an 06 Buick lacrosse with the 3.8l. I have just installed a new fuel pump, fuel pump wiring pigtails, new oreilllys crankshaft and camshaft sensors, new plug wires and battery.

Just as before I installed these parts, sometimes it will crank over and just barely run a second then die. Other times like yesterday after I installed the new battery it fired right up and ran good for 10 minutes then started sputtering and died like it ran out of fuel, or the computer cut the fuel pump off possibly. It started right back up and ran long enough to drive in the garage before it did the same thing again. When I try it today the fuel pump doesn’t come on when you turn the key on so it just barely starts and dies.

is there something I’m overlooking that would make the pcm cut the fuel pump off? I tried unplugging the MAF sensor today but that made no change. It doesnt give me any codes for anything. Any help on where to look or suggestions are appreciated. -Ryan

Forgot to mention, I did swap the fuel pump relay with another one with no change

Maybe some back story is needed. Was it running fine and then something happened. Do we know what the fuel pressure is? If the pump does not work you will not get a hit at all. How are you testing things?
Did we try spraying ether or carb cleaner in the intake to see if it hit?
Sounds like you may have a bad ground or the ICM is going out. Either way we need to do proper testing to narrow down the problem.

What carfixer007 said ^^^^^^^^

For the backstory on the car- the car has only 52k miles. about 2 years ago my mom was driving it and it just died all of a sudden. I went to pick her up and tried to start it and it fired right up, drove about 10 miles home and put it in the garage. The next day tried to start it and it would crank and crank and never fire. So the car has set until now.

when starting to try to find the problem I realized when I turned the key on I couldn’t hear the fuel pump run. The car would run with a gas soaked rag in the intake though. That’* why I replaced the pump, and in the past a mouse had chewed some wires off where they go into the pump so I wanted to drop the tank to check that previous repair. That’* why I changed the pigtails to the pump.

When that didn’t work I read where it could possibly be a crankshaft or camshaft sensor so I changed those. After I changed the camshaft sensor is the first time I turned the key on and the fuel pump ran and the car started and ran…about 6 minutes until it sputtered and died.

When the car cranks now but barely hits and dies, I have checked the bleeder valve on the fuel rail and fuel barely dribbles out. Has no pressure hardly at all. When this happens I have checked for power at the fuel pump relay with a test light and have power to one prong with the key on (can’t remember which one, can double check that). But never get power to any other prong whether cranking or not. Right now I am just working with a test light, but will get a fuel psi gauge and multimeter so I can get deeper into this.

I had been jumping the car off all the time because the battery was dead. After I put the new battery on was the longest the car ran, about 10-12 minutes until it sputtered like it ran out of fuel and died. It currently just cranks and might hit once or twice but will not start. I kind of wondered if I unhooked the battery for awhile if it would run for 10 minutes or so again but haven’t tried that yet. I will see if I can find all the grounds I can and clean them up as well. I took a look at the pcm just to check for chewed wires or anything but didn’t find any problems there. Thanks for the replies so far!

You MUST clean the grounds to the body and frame or you may never fix this.

https://charm.li/Buick/2006/LaCrosse...on%20Diagrams/

What carfixer007 said ^^^^^^^^

. . . and: what is the voltage reading at the battery while the car is running?

I definitely agree on the fuel pressure gauge. From what I can tell so far, you could have saved yourself the expense and trouble of changing the cam and crank sensors if you had this before you changed them.

If I had to guess what our future selves will learn later: I bet more wiring issues. One prong out of four on a relay that is energized only when the ignition is on tells me that the BCM is calling for fuel pump, but there is no load supply to the load side of the relay.