Help, AFM trouble?

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Car runs fine when cold though using lots of gas and low on power. Shut it off once it warms up and restart and it misfires bad. Unplugging AFM does not change anything even when running "normal". No change in rpm, sound, not even a check engine light. Should sc400 start and run without check engine light if MAF is unplugged? Does this point to bad AFM or bad computer? Absolutely no codes. First question? Should I get a code when unplugging MAF? Does no code point to bad computer?
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Can someone answer please? If you unplug your MAF on 93-65 ls400/sc400, does check engine light come on?
lol. Thats first thing I did. And searched forums. If I can just get answer to that question, I can tell if MAF or computer is culprit.
If you can get your hands on a computer to test with it may save some dollars. Do you have the check engine light on before you start the car.

Could be a wiring fault.
Now it's worse. I found that by unplugging AFM it ran fine although it was idling really high. So I assumed AFM was culprit..I ordered another from ebay that was supposedly tested. In the meantime I kept having problem starting car even with full battery. I added a ground to chassis and changed terminal. I also added HID headlights. The HIDs shorted headlamp fuses which were only rated at 15 AMPs. However, when I added the ground and changed both battery and the terminals, the car started however it ran like garbage even with AFM unplugged. Still no check engine light but the odd thing is it idles at 800 rpm like it is supposed to although with a misfire. I don't see how a shorted headlight fuse or added ground should cause it to run like crap unless the ECU is definitely culprit. I have the only sc400 in the country where I live so no chance of trying other ECU. Sad part is, the ecu that is in there is one that was already rebuilt and tested a few years ago. UNtil now, it hadn't been problematic but there were melted wires going to AFM that had to be repaired by my mechanic shortly before I took possesion of the car so I can only surmise the short killed ECU again?Check engine light will illuminate when turning the key but turns off when car starts.