The once in 7 to 10 day stalling has finally come full term, and the car will no longer start, though it tries.

Last and only code pulled was P0171 (bank 2 too lean)
Over the past 3 months, I've replaced the following:
Fuel pump relay
Fuel Filter
All vacuum lines - also checked for leaks with propane and carb cleaner
Cleaned the MAF and TPS, AIC, and throttle body.

Up until today, it would stall about once /week and start back up.
Over the past week this became more frequent and took more time to restart.

I checked fuel pressure: At keyswitch position 2, the pump turns on briefly, pressurizing to about 15 psi, then shuts off. After the engine is started, the pressure builds up to about 40 psi and seems to stay there (using an old tire gauge to measure).

To see if power to the fuel pump is intermittent, I attached a voltmeter at the pump and monitored it from the drivers seat while driving around. During stalling, 12 volts was still at the pump.

Yesterday it would cut out occasionally while cruising and was sometimes slow to start. Car was garaged overnite, and today, it cranked, but idled rough (didn't want to rev)and brown/white smoke was coming out the exhaust, then died after about 30 secs. Now it won't start, though it tries.

I might have a new code set now, but won't have access to a reader before Mon.
If anyone has any suggestions, they sure would be appreciated.

Thanks,
Kcarl