1997, 5.7, Misfire at idle, cylinder 2+5

[superrod29]

1997 C1500 5.7 350. has around 277,*** miles. (she's very clean) since i got the truck in February, i have been chasing a random misfire at idle. All ignition components have been replaced/upgraded (ac delco gold plugs, msd street fire distributor and wires, accel supercoil), upper and lower intake gaskets (and all of the smaller gaskets and o rings) , spider injector system bench tested and found to be working "properly", compression test showed equal values +/- 2-3 psi across the board, Timing chain and components have been replaced, along with harmonic balancer and other pulleys. i do have the scan visual to show the two misfires. any ideas on what it could be? im half tempted to mess with the valvetrain, but if im digging in that deep im just going to rebuild the engine. i have yet to do a leakdown test but have the tool, just dont have the time to get it done at this moment. im sure the leakdown test will show something but im mentally exhausted from this chase. Any help would be appreciated!

 

[GoToGuy]

How do you bench test a poppet fuel injection?

 

[beachman]

Had a very similar situation on my 97 C1500 and found out that it was a fuel regulator that was leaking and causing cylinders 5 & 3 to flood at idle and misfire even though the regulator was on the right side of engine. Like yourself, did a lot of trouble shooting before this was found.