Intermittent power loss problem (archive)

I need help diagnosing this problem. I have a 1985 325e. It has a Dinan chip, stock intake, aftermarket cat and muffler but this problem was present before the Dinan chip and aftermarket Cat converter (the chip and converter made no difference) also it ran fine after the muffler install (the muffler made no difference). I do regular maintenance, Fuel filter every January, synthetic oil every 5k for the past 80k miles, the O2 sensor is almost 1 year old as is the new Cat. Has like new gas mileage and more power than new with the dinan chip. Last smog check had nearly .02% CO, almost nothing. 92 octaine Moble gas. I have 200K miles and have had this problem for about 30k miles. It is not deteriorating at this point. The problem is always when hot (happens 50% of the time), I can start the car. It runs really smooth but it idles a little low and revs really slow. Almost like there is some type of blockage in the intake system. It varies in intensity too. Some times you can drive the car while it is doing this. There is no smoke comming from the exhaust but there is about as much power available as if you removed a spark plug. Again it runs smoother than when it is running correctly in this condition. And it smells like it is runing really hot too (cat converter hot, not coolant hot). It never does it when cold, only hot or warm. Anyway to make it stop doing this, I turn the car off for about 5 seconds then I turn the key on to position 2 for about 5 seconds, then I turn the car over. It usually works the first time, sometimes the second try never more than a third try. Once it is running correctly it will not do this while the car is already running. It only happens when you first start it when hot or warm and not every time (say 50% of the time it acts up).

My diagnosis (so far)
To me it feels like a lean condition and possibly the air mass sensor is jamming shut. I looked at it today and it moves freely though. Of course it was cold at that time, expansion perhaps? Because all cylinders run lean, maybe the fuel pump or pressure regulator? The regulator works fine (shuts off the fuel), when coasting with the clutch out at moderate RPM. Could I have a fuel leak or some other way air is getting in the fuel line? I don't smell anything like that. Do those fuel dampeners ever clog? Any thoughts?

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