mine did the same thing, but mines 4.8, it would bearly start some times, or some times it woudnt start at all, and it ran like **** till i reved it up a few times. i got tired of that **** so i went to my local gm dealer, they ran a dinostics test on it, and it was the fuel pressure regulator, all togather the bill was like 175$ i think. but im glad i took it to my local gm dealer, cause i was just about to order a new fuel pump and drop my gas tank and put the new one in, but then i started thinkin, it would be the cheapset and fastest to get a dinostics test ran on it to pin point the prolbem.

 

Wait, Where is fuel pressure regulator at? mine 2006 5.3. Did you replace the fuel pressure regulator?

 

I wonder anyone from here who have walbro 255lph and havent use it and want to sell? Let me know the price please!

 

I want to know how can I test fuel pressure tester? Tell me how. Do I have fuel pressure regulator in my tank? If yes, how can I check if its bad and I can get new one. Where I can get those? give me a link would be helpful. It must be returnless? It is good for being returnless on 2006 model? I want to know which FPR or fuel pump is bad. Also do I have fuel filter in tank? Somebody told me. I puzzled. All I know of that I not have one on driver side frame where fuel filter at. Since my truck is newer model.

 

I have some info. My truck wont start anymore on yesterday. So it is fuel pump needs to be replace and not need replace for fuel pressure regulator also? UNTIL this morning it crank up work. ABout less 30 minutes turn off. My cousin listen if the fuel pump make it noise. Sounds like to get gas to flow. Before I crank up and it wont run. I thought if no noise on fuel pump mean wont run right? But they still nosie mean able to run? I need to know which one is bad fuel pump or fpr?

 

You have the returnless system which doesn't have an external regulator, actually I don't think that the returnless systems even have a serviceable fpr. The pump may still make noise and be no good, it's possible that it's trying to turn but not pumping enough. You need to get your hands on a mechanical gauge and hook it to the test port on the fuel rail, then crank the engine and observe fuel pressure. Search for the exact number, but I believe that you want somewhere in the neighborhood of 58-60 psi.

 

just turn your key to the ON position and go poke your schrader valve to see if your getting good pressure any

 

you can buy a pressure gauge to use on your schrader valve for $16 at harbor freight

 

worth every penny

 

Okay after I read your comment. I ahead try do on my truck. Yes it seem power pressure gas air bleed out.