I have a 93 Sc400 and it has a problem accelerating from a dead stop. I cleaned out MAF.
If the MAF sensor is disconnected there is no accelerating problem, but check engine light it on.
I replaced the MAF sensor from a pick n pull.. I replaced the MAF sensor (black part only) and the check engine light goes away but the problem still there. What can it be?

 

Could be a number of things. When you say trouble accelerating from a dead stop I think transmission. Is the tranny slipping?

 

No. It doesnt seem like its the tranny. When i unplugged the MAF i was able to accelerate normally with the check engine light on of course.

 

Well, that means, 1. your MAF is bad, 2. Your replacement maf is bad. 3. CPU is bad. 4. There is something mechanically wrong.

BTW CHANGE THE WHOLE MAF!

 

I fought with this issue for a long time on my old sc, ended up being a damaged spark plug wire that wasn't making good contact with the plug, make sure they're all good.

 

I also fought this. I had two issues. First my timing belt had skipped a tooth on one side. Once that was fixed it was ok for abut 1/2 a day. Turned out the plug wires and coils had gone brittle and cracked, and were leaking spark. Really check the wires, coils, and plugs before going on the wild goose chase of all the other possible causes.

 

These guys are right!^ start cheap work your way up!