random misfire when first applying throttle 3.0

[freedo]

i have a 2001 3.0 5spd with 235k on it. just recently it started doing this weird stutter (misfire) when first applying throttle to accelerate from a stop and after shifting gears. it is no consistent and after the quick stutter and drives and cruises like normal. i thought at first it was load related but i am able to replicate it at a complete stop and in neutral by just give it a little gas. doesnt happen every time though and has not thrown any misfire codes. current codes are for a bad secondary air pump and for the O2 sensors. it had a fuel pressure code for low fuel but that self cleared and hasnt been back after 200 miles of driving. i have emptied a entire can of brake clean around the intake and noticed no change in idle (i made sure it was the flammable stuff) i am stumped on where to look next. plugs were done 10,000 miles ago and still look good, i dont hear any obvious vacuum leaks and found none with the brake clean. any ideas on where to look next? i do have a oil leak under the intake somewhere so i am planning on pulling the intake to investigate and replace stuff so if anyone has a list of items i should replace once the intake is off please let me know. thanks for any help