drag0n439

I have a 96 jeep Cherokee, 4.0l sport @ 177k miles

i just replaced my cracked manifold with a brand new one(with better gasket then the paper one that came with the kit), my intake; one from a Pic-a-part(when i took my old intake off the positioning tab towards the front was broken off,so i got one from a pic a part, in which i thought it was for a bolt, my old intake is still good i can get jb weld for that broken tab and re-use if need to), and my o-rings for my fuel injectors.
one bad thing that happened when i originally got it together that same positioning tab was not positioned cause of my dumb *** and caused a major vacuum leak causing my car to start at 2k rpm and jump to 2.5 in half a sec causing my new manifold to glow red hot.


plug,router, wires, cap replaced @ 20k miles ago and checked them last week
axes,wheel bearings,new routers about 15k ago
fuel filter about 5k ago
front drive shaft is out cause it was bad a while ago and just have not replaced it yet.

other major repairs that probably dont apply to my issue
coolent system(radiator,hoses,thermostat + housing,water pump)

Problem :
i'm getting cylinder mis-fire code on #1,2,and 6

when it starts it shakes real bad, when idle not so bad, i also hear a wiseling/winding sound when coming to a stop now.
when i drive i don't feel it at all.
it does not back fire
Idle RPM approx 1100rpm (which is high) i think it needs to be around 900-1000rpms

the shaking sounds like the catalytic converter rattling around when starting and turning off the engine(which was replaced about 10k miles ago)

ive been told so far
timing belt
motor mounts (which are indeed bad and will replace this weekend)
vacuum leak

so when i replace the motor mounts and this problem still occurs. what other suggestions?


p.s. im not a very good mechanic, im still learning in the novice age. lol
cheap repair suggestions, if possible, are always welcome