05 5.3 Hard Start

[bfr57]

5.3l, 2005 Avalanche, 63K miles, flex fuel option but not used, no codes. Truck cranks long when warm, not as bad as when cold. Doesn't sputter or miss once started, runs great, mileage constant. Have tried letting pressure build w/key on before start w/no difference. Condition up to now was just hit the key and would start. Been through a couple tanks of gas from different stations, so ruling out gas problem. No FPR or filter; must all be contained in pump now? Haven't done FP test as I don't have a gauge. Should I be concerned? Don't want wife and kids stranded somewhere!

[rodram]

.. I understand your concern about the possibility of leaving your wife and kids stranded somewhere... you certainly have your priorities straight, my friend...

 

.. yes, I would be concerned.. depending on where you are living, old man winter is coming, just around the corner.

 

.. I would definitely get the fuel pressure checked.... I am not sure of the fuel pressure required for your 5.3L to start/run reliably, but the 5.7L Vortecs (and other Vortecs) all needed 61 to 66 psi, and this was critical..... as my truck became harder to start the fuel pressure was slightly below 60 (in the high 50's) and by the time I gave up on it and had the pump replaced it was down to about 55 psi...... new pump now and no problems getting it started!!

 

.. if that is not the issue, then you may have injector issues, but faulty injectors would likely cause random misfire codes to show up and cause hesitation while driving

 

.. short answer, YES GET YOUR FUEL PRESSURE CHECKED.

[asilverblazer]

Change the fuel pressure regulator, very common problem and your symptoms describe it perfectly.

[redvett]

Flex fuel vehicles use a return fuel system and has an external fuel filter and a FPR outside the fuel tank unlike the return-less systems. Change the filter and check the FPR vacuum hose for fuel.

[Flyingbrian]

If it is Flex Fuel it has a filter. That being said CHECK THAT FUEL PRESSUE will to bet you will find it just a few pounds under min spec

[bfr57]

I've searched for both a fuel regulator (on fuel rail) and filter (inside frame rail), but haven't found either. Went to local Autozone and they don't list either in their part system. I read somewhere they incorporated all into fuel pump?