Toyota Repair: TOYOTA LAND CRUISER 80 SERIES 4.5 1993 MODEL, mass airflow meter, toyota land cruiser

Question
This is an import model from Japan, RHD, Automatic, which I bought as a second hand vehicle and have done already 450 000 kilometers without any problems up until the last few months. I have first notice a significant decrease in performance/power and have noticed the rev counter drops a few rpm's and then pick up again, and you could feel the slight slack and then gain in power/speed as you go without any acceleration or deceleration at all. Then on one trip during November 2010 this become suddenly more and more a problem and then I noticed that when the rpm's is above 2000 it will run more smoothly but below 2000 rpm it was a real problem to keep it going. hen I could hear the in-tank fuel pump start making a noise as well and thought that this was my problem. I could only get an appointment for a service in early January 2011 and therefore the vehicle has been standing from beginning December a great frustration for me. I really could not do anything without my Cruiser and my work is standing still. The local Toyota workshops here in Namibia (Windhoek) do not work on an import vehicles some bureaucratic #**???!!(speak my mind)policy, but in the mean time all their vehicles sold in Namibia is imports including all the Cruisers, Lexuses name them! **&%#$ idiots in my eyes, but we do have one Garage that do specialize in these import Toyota's and does help us a lot. They did service the vehicle replace the in tank fuel pump but the problems still prevails. Then they told me the problem is the Mass Airflow Meter, something was wrong/loose inside this was fixed, and I receive my Cruiser back on the 4th of Feb'11. On Saturday I drive the vehicle from home to work and when I start it, it did start and run but as soon as you depress the accelerator there is no power, and I battle to get it going, I made it to the workplace and that evening let it idle for about 15 minutes before I climb in and drive home. This was the best performance I had with my Cruiser for a long time and gunned it a little bit on the freeway to check it out she easily went to 140km/h and the pulling was excellent. The next morning a different story, but this time the power was now where to be found it is if she does not get enough fuel and the rev's just does not pick up, I then start to fiddle with the plug that went onto the air flow meter and it seems that as soon as I move it to one direction the engine runs smoothly and the rev's pick up normally, but this is for a short distance and then the same thing again now power. When I switch the engine off and then start it again it seems that it is Ok for the first few meters and then back to normal again. I also noticed that the engine warning light come on as well something that I have never experienced in the past. Another noticeable thing is when this problem started the Speedo Cruise was also not working at all and they have told me that this is one thing that they could not repair, but now suddenly after I receive the vehicle back the Speedo Cruise is working, and they did not work on it. This Cruiser have taken me home many times during very bad trips especially in Angola where most off the other vehicles have failed or gives us problems, and actually become part of me, nobody really understand this but if you rely on something that never failed you in the past, there is not even a thinking to buying something else this vehicle must just be sorted out and I need some advice to do this.

Answer
You need to check for any trouble codes that may be in the computer, you can do this yourself and tell me what you found.
Under the hood locate the diagnostic connector(it will say "diagnostic" on it) open the cover and look inside, there is a terminal diagram there, locate the terminals TE1 and E1 and with the key on put a short jumper wire between these two terminals, the engine light will start to blink giving you a code number, for example a code 25 would be two blinks followed by five and so on, there may be more than one code so let them repeat a few times to sort them out.