As your ECM is controlling both the carb and the lockup then they can also malfunction if or when the ECM is not working properly. At the same time there could also be numbers of other things that could cause the same symptoms.
If your ECM is not working properly it will not controll the air fuel solenoid inside the carb. When the solenoid is not working it's in the "up" position that gives the primairies a full rich condition. That is if the ECM is not sending out any signals, if it's sending out a 12v signal all the time the carb will be in a full lean condition if that is even possible?
You can check if your A/F solenoid is working by briefly making contact between the A/F solenoid with a wires to a 9v battery. If you put a small allen wrench down the left or right openings above the carb next to the idle air screw you can see the wrench jump up and down when the solenoid is energized by the 9v battery. If the wrench is not moving the solenoid needs to be replaced, if it does work the poblem is somewhere else.. (all credits go to Sensei for the test
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For the lockup. There are 3 wires, A, B and D. A is a constant 12v source (don't know if that's from the ECM). B activates the lockup solenoid by grounding the wire when you hit the brakes or under a certain speed (ECM controlled) otherwise there is also 12v on the wire. Wire D is for the upper gear switch, don't remember how that works. With the ECM not working I think wire B will not get the 12v and ground all the time. So I think wire A is also not getting 12v to make things save. And this is easy to check of course.
Two things from the top of my heads, I think the best you can do it check the trouble shooting in your 81 service manual to find the problem!
Greetings Peter
