Toyota Repair: Loosing power, exhaust gases, cat converter

Question
I've been having a problem with my 1993 Toyota Pick-up (4-cyl., 22RE, manual trans.) for a few months now and nobody can seem to fix it. When I'm driving, doesn't matter if the engine is hot or cold, it'll run very sluggish. I'll step on the gas to accelerate and it will hardly feel like it's going. Secondly (this is very scary), I'll be driving down the road and without warning, the check engine light will illuminate and the truck would loose all power and shut down. Immediately following that, I'm able to start it back up and it'll run for awhile before it does it again (it's very intermitent). Also when that happens, I'll hear a buzzing noise coming from the lower-right passenger side compartment when the light comes on; then it will go away (maybe from the computer). I've taken my truck to three mechanics (one being a certified Toyota shop), and nobody can find a problem. No codes will show on the diagnostic tests. That's very mind boggling because I have a serious problem here. I've owned my truck since 1995 and I've always taken great care of it. It has just over 90k miles and had a fresh tune-up a couple years ago. Please help, I have nowhere else to go. I'll be lucky if I don't get into an accident when the truck shuts down again. Thanks for your help.


Answer
If the check engine light comes on there should be a trouble code in the computer so I don't understand why there would be no code logged in it, but anyway I'll try my best to help you.
There is possibly a problem with the catalityc converter, it may be disintegrating and getting clogged up, this would explain the loss of power and stalling, the exhaust gases can not exit through the muffler and chokes the engine, not 100% sure but I've seen it happen, if that is the case the cat converter and muffler need to be replaced, try removing the converter for inspection, if it's coming apart you will see a lot of the inside material fall out of it, it will look like a bunch of small gray pellets, that's my best guess based on the information I have.