Burnt Capacitors On A9l Board

there are three 47uf 16v capacitors on the circuit board. 2 of them each have 1 leg burnt off. im not an electronics guru by no means so for those guys here that are here are some questions/background. Ive been having a low rpm miss for a while and couldnt pull codes. I checked pin 40, 46, & 60. they all had 0.2 ohms. I decided to move on thinking the A9L was ok. then things went nuts. what i mean is the eng started running so rich it had black smoke like a diesel from the exhaust and I actually had to turn the fuel pump off to get it to run sitting in the drive way. I sawped out the A9L ECM with the original A9P and it ran but the miss is still there. Found i bent all the exhaust valves so thats another issue. Are the caps a common failure with the A9L? if so, were is a good place to find these caps? is there any diference between an A9L & A9P wiring harness that may have been what fried the A9L or are they interchangable? If i replace the capacitors is there a way to function check the eec since the car is going to be down for a while?

thanks for the info on the caps. just so we are clear about harnesses and what i did. i took the engine harness from my red 90 fox that was a factory auto and put it in the black car that is a factory 5 speed the O2 harness is the factor 5 speed car plugged into the factory auto harness. I cut the power wire to the heaters and hooked that up to a seperate power suply so that when I have the power turned on to the eec for tuning purposes im not heating up the O2 sensors. what is diferent about the O2 harness that might cuse a problem switching from an a9p to a9l if any

thanks again for the info