05yukon xl denali 6.0 hard start

[jasonb100272]

it developed the hard start last winter. I just replaced all injectors with new Delphi within 3 months (after 2 were leaking) and new Delphi fuel pump 1 month ago. once I replaced the fuel pump it was like new. started in 2 seconds but went back to having to cycle the key 3-4 times or hold down the pedal. I am at a loss ? could it be a fuel pressure regulator? or intake gasket? I also have po420-po430 in both bank 1 and bank 2. I replaced all o2 sensors. is this a bad cat? and a occasional miss fire. within 2yrs or 20k I did wires, plugs, switched tranny and diffs with BG products and transfer with (smurf ) ac delco fluid. my plan is to drive till the wheels fall off but this drives me crazy with these repairs and still no long term solution. any ideas where I can start. I also have ran 44k twice in the last year? but #1 has a broken stud but goes away in a minute or 2

 

[Doubeleive]

there is a fuel pressure control module but that doesn't explain it working fine after replacing the pump, you could maybe have plugged cat's you could have a backpressure test done. you could do a fuel pressure test just to verify fuel pressure is correct also.

 

[jasonb100272]

ok thanks for the tip