No I have not touched the cats, I did have the O2 sensors replaced a few years ago. My thoughts related to the injectors are that maybe there could be a fault in the wiring and that may have damaged the ECU. Once I replaced the ECU the car ran fine for a while then very suddenly it started acting as it did before which in all likely hood means the ECU is fried again. I did do a search the other day for things that might kill an ECU and the injector wiring harness was near the top of the list. It does seem odd though if that were the issue one would think that one or more cylinders would misfire due to injector problems but it seems to be misreading the air flow when the MAF is connected or at least that was what it was doing before and seems the same now. The result was the ECU was not giving the engine enough fuel and caused a very lean condition.If it were the injectors or the the intake manifold, disconnecting the MAF would not likely change the performance. Did you ever do anything with the catalytic converters?
I was going to inspect the wiring today but of course it started pouring down the rain just as I was about to get started so it will have to wait. I also plan to get under the car and check the O2 sensor wiring. The reason I suspect the injector harness is that I had a coolant leak a while back and had to replace the intake which mean I had to fiddle with all those injector connections and then of course the new intake was a little different than the old one and did not seat properly causing me to take it off and put it back on two more times before I got it to work and each time having to handle all of those injector connections. about 300 miles after this repair the ECU failed and about 200 miles after replacing it it seems to have failed again. Combine that with my search turning up injector harness as a possible culprit and it seems a valid possibility though may be hard to locate and of course it may be something totally different.