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 7, 2014

Having never done it myself, I would expect you will need at least half to three quarters of the depth of the tank to get it out. At some point the sending unit will need to laid over on its side. At that point you are essentially out and should not need much more clearance. Make sure that the bed of the truck is not hitting any body panel and damaging it.

Doug_Scott · October 10, 2014

Is there any way to "adjust" the length by loosening any of the components and collapsing the assembly? Or is the entire assembly built in such a way that you cannot loosen any parts?

For example, if you have two steel lines that are connected via a rubber hose secured with two hose clamps, you could loosen the clamps and pull the steel lines away from each other to lengthen the assembly, or push them together to shorten the length, and tighten the clamps to secure it again.

Does the old unit have those rubber feet you mentioned, or is there any spot on the original pump where they could have been attached? Does the bottom of the new pump have sharp edges that make the rubber feet necessary to prevent the pump cutting the bottom of the tank?

Doug_Scott · October 3, 2014

Not sure when GM started doing it, but, it is not unusual for the truck to keep cranking after letting off the key until the engine starts, provided you let off the key in less than a second or so. I can sometimes get my seatbelt on while truck is still cranking with me not touching the key. My last two Pontiacs did that as well.

As for your truck, check fuel pump. Easy enough to check, turn key on, and check for fuel pressure at the Schrader valve.

gmc70 · October 5, 2014

I lifted the bed as much as possible, and checked power at the pump and I can hear the pump engage when the key is turned so could the pump be good?

Thanks for the t-shirt tip I'm sure my wife wouldn't appreciate the gas smell..

I would have checked the fuel pump control module. Bud who works for gm dealer says they like to go out at 100k or so. Gives symptoms of bad pump but the module controls the pump. Took mine out and had standing water in it. A lot easier to check that then the pump

I will check the fuel pump control module I might as well check everything.

gmc70 · October 10, 2014

The tank was empty that was the problem, the gauge said it had a little over a quarter tank left so the sending unit was bad, I bought a Delphi FG0909 pump but it wont seat in the tank it is about 1/4 inch to tall, the pump has these removable rubber feet on the bottom they are about 1/8 inch thick I wonder if I need those.

I also have the tank up on blocks but the pump wont seat all the way.

any ideas?

Doug_Scott · October 5, 2014

I lifted the bed as much as possible, and checked power at the pump and I can hear the pump engage when the key is turned so could the pump be good?

Thanks for the t-shirt tip I'm sure my wife wouldn't appreciate the gas smell..

I will check the fuel pump control module I might as well check everything.

If the pump is running, and you are not getting any fuel out from it, then it is likely not pumping. Verify the fuel filter is not plugged as well if you have not already. You can disconnect the fuel line from the filter, point the line from the tank into a bucket or some receptacle to catch the gas, and turn the key on. Fuel should be coming out with some force behind it. This is a two person job, one will likely get dirty, the other won't. Do not leave the key on unless you have a large catch can. Not sure if they still do it or not, but, there used to be a spec for how much fuel is pumped in so many seconds. I would just check to see if it comes out under force for now.

gmc70 · October 3, 2014

Could it be the relay?

gmc70 · October 3, 2014

Not sure when GM started doing it, but, it is not unusual for the truck to keep cranking after letting off the key until the engine starts, provided you let off the key in less than a second or so. I can sometimes get my seatbelt on while truck is still cranking with me not touching the key. My last two Pontiacs did that as well.

As for your truck, check fuel pump. Easy enough to check, turn key on, and check for fuel pressure at the Schrader valve.

Thanks man I will check that in the am.

gmc70 · October 14, 2014

Truck is fixed, new pump worked, thanks for all the info..

gmc70 · October 10, 2014

When I go to Oreillys website its the same model# pump for my truck with the vin letter 0.

could the tank be cold and that's why its not giving?

Colossus · October 4, 2014

If you have to pull the tank, you might as well replace the entire module in there, don't just do the pump only.

Doug_Scott · October 10, 2014

Is the pump the same length as the old one? When you say the tank is up on blocks, do you mean the blocks are under the where the pump is going? If so, rotate the tank 90 degrees and see if the pump fits now.

I give you credit, its not everyone that would post that they ran out of gas. The clue should have been the weight of the tank when you dropped it. I see that you mentioned the tank felt light to you.

TJMaine · October 3, 2014

Mine did this.... Was the fuel pump control module or whatever the heck you call it... up under the bed... 100$ part from GM and 100$ program from GM dealer ( your prices and issues may vary )

gmc70 · October 10, 2014

I put a couple 2x4 pieces under the tank thinking mabey the tank would give a little and the pump would go in.

There is no shame in the fuel level, the gauge said it was over a quarter of tank I trusted the gauge why wouldn't I, it has been lower than a 1/4 tank before. hell I trusted this truck I spent 17k on this damn thing it should be trust worthy lol.

no the new pump is taller than the one that was in the tank not by much but it is, why would all the auto parts sites say this is the correct pump, very frustrating!

TJMaine · October 8, 2014

Not to be rude, but i am still baffled you havent checked all the cheaper and easier things first or posted any codes or anything..... I was ready to do the same thing you were, then I took that damn Fuel Pump control module out and it was pissing water out of it... replaced and problem solved.... ( after trip to dealer for program )