2007 gmc sierra ltz 5.3 died while driving

gmc70 · October 3, 2014

hey guys, great site

I was driving home tonight with my sons 14-6 & 8 weeks, when all of the sudden I noticed my gas pedal went soft I looked down and there's no rpms so I throw in in neutral and try to start it but it wont start so I pull over and put it in park and try again, but it wont start it just turns over, I sat there and tried a few more times but no luck, so I pop the hood and check everything over and don't see anything out of place so I let it sit for a few and try again but still just turns over, So I called my father in law and we towed it home, it has gas and oil it wasn't hot, I have no Idea what it could be, the truck is a 2007 GMC sierra slt with the 5.3 engine,

Any ideas what it could be? fuel pump?

Doug_Scott · October 5, 2014

Chances are the nut has broken free. You may want to try to cut the head off the bolt, and once the box is off, fix the broken nut. There is also a fair amount of flex in the mounts, and if only one is still on, you may be able to lift the box high enough to get the pump out.

How much gas is in the tank? Gas weighs somewhere between 6 and 6.75 pounds per gallon. Keep that in mind when trying to drop the tank.

gmc70 · October 5, 2014

_{There is about a quarter tank in it, do you think it would it be easier to try to lift the bed or should I just drop the tank? The location of the bolt would make it very hard to grind it off I would have to use something small like a dremel, That would take awhile....}

gmc70 · October 10, 2014

Delphi FG1059 Fuel Module is shown to fit this truck, Can anyone confirm this?

2007 GMC SLT 5.3 flex, 4WD, 78.7 bed VIN 0, 4 dr extended cab.

gmc70 · October 3, 2014

Borrowed a tester from AZ and hooked it up turned the truck over and no pressure.

So its the fuel pump.

Doug_Scott · October 5, 2014

From what I can find, your gas tank holds somewhere between 26 and 27 US gallons. At a quarter tank, that will be about 6.5 gallons left. Each gallon weighs approx. 6.5 pounds, so you have about 43 pounds of fuel in the tank. It is not overwhelmingly heavy, but, trying to hold a tank with 40 pounds of fuel moving around in it can be a bit daunting if you are on your own. Tank is also plastic, and I am not sure how it behaves if it happens to drop from a couple feet with 40 pounds of fuel in it.

If you drop the tank, have someone help. And once the tank is out, have enough gas cans around to hold the fuel in the tank, and dump as much of the fuel out before trying to put it back in. Make sure you hose the top of the tank off before pulling the sending unit and pump. You may want to empty the tank into a big bucket, and then either fill tank back up after installing from that bucket. If you do, make sure bucket is clean, and when transferring it back into the tank, put an old t-shirt over the funnel to filter out any crap you missing when cleaning the tank off. Don't cut the skirt, run the fuel through a double layer of t-shirt. BTW, do not toss it into the washing machine while it is wet, and do not just leave it all bunched up on the floor of the garage. If you want to keep the shirt, hang it up outside to dry, then hose it off a few times, let it dry again, hose it off again, and if the smell of the fuel is still strong, let it air some more. If you just toss it into the washing machine it can damage the internals, and will for sure transfer that gas smell into everything you wash for the next couple of months. I would just let it dry outside, and leave it there till next garbage day, and at that time, throw it out.

gmc70 · October 7, 2014

Well I ordered the new pump a Delphi, it should be here at the latest wed, I also tilted the bed up and I can only get it so far with that other bolt still in, any idea how much clearance would I need to replace that pump under the bed with it tilted?