BIG PROBLEMS after motor swap 98 explorer xlt sohc

[98xploder]

i have a 98 explorer, just swapped a 97 sohc 4.0 motor in, and im having issues. anywhere between idle and 2500 rpm it will lose power, misfire, and make popping noises out the exhaust. if i just floor the truck or back all the way out of the gas, it will smooth out. i dont know if its a vacuum issue like i previously thought. i plugged my one stray vacuum line *which went to a coolant bypass valve (which isnt there) and i dont think there are any other vacuum leaks. i sprayed down the intake with starting fluid to check for leaks, and there are none. there are no check engine lights on, so im wondering. maf? tps? bad injectors? i cut my hand pretty bad,so i cant afford to keep throwing parts at this truck working one handed. (so i have use of my right hand) any insight would be very helpful, as i cant afford to sit here and throw parts at the thing till im blue in the face. i have parts i could pull off my other motor, i just dont want to spend another 2 weeks getting this done.

almost forgot to mention. when i pull up to stop lights, the rpms drop down to about 500 and it bogs off the line until i floor it. after about 2500 rpm its fine, but when i ease off the throttle, it starts popping and whatnot.

i think my major issues are with the vacuum lines. the truck throws check engine codes saying bank 1 and 2 are both running rich... can someone help me out with a few engine bay pics so i can get an idea if my vacuum lines are all backwards? or at least a color coded vacuum diagram? i cant figure this thing out at all, and in the other forums, people are just sooo quick to blow me off. i am having a genuine problem as this is my only vehicle now, and i know it cant be good driving it around like i am. a quick response would be MUCH appreciated.

[Johnny Mullet]

Usually a bad sensor will throw off a code. Have you hooked a fuel pressure guage to it and monitored pressure when it acts up?

Also, this may sound stupid, but the PCM is used to all the stored memory settings from the old engine and maybe try resetting it by disconnecting the battery for like 15 minutes and try a drive cycle (test drive) to see if it straightens out.

If none of this works, then start with the basics...........

Check spark at all cylinders.
Recheck vacuum lines.
Check compression on all cylinders.

[98xploder]

i got it sorted the vacuum harness was all ass backwards. i gotta let it run for a few though, cuz its still idling rough..

[Johnny Mullet]

Let us know how it goes!