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CIS-E _still_ ill (was '87 4kq FI trouble)

     Recap:  car runs like crap for about four minutes. ***Much*** extra 
     fuel coming from somewhere. Once temp gauge moves a tick or two, it 
     suddenly runs perfectly--just like I'm used to.
     Previous suggestions:
     O2 sensor
     Idle switch
     Thermo time switch
     Stuck-open cold-start valve
     What I've checked/found so far:
     O2 sensor (engine warm):  (no dwell/frequency on my DMM) ~0.700 volts 
     for one second, drops to ~0.550 volts for 1/2 second, up to ~0.750 
     volts for 1/2 second, back down to 0.700 volts, starts over. Note:  a 
     handy way to check WOT operation is to look for an 02 spike (hold 
     throttle open by hand to ~4k RPM, actuate switch by hand).
     Idle switch:  ~4 ohm resistance at "idle," infinite resistance 
     otherwise. Good or bad?
     Thermo time switch:  my understanding is that this controls the CS 
     valve below 35 dC and _only while cranking_. Since the car starts 
     instantly, this should have no bearing. Also, disconnecting (before or 
     after starting) it makes no difference.
     Pulling the CIS fuse while it's running poorly "fixes" it. This at 
     least allows a ~smooth warm-up (takes about 4 minutes before it'll run 
     Noted on this AM's (11 hours engine off, 50 dF, 10 dC) startup:
     Pressure regulator:  18.2 ohm resistance (cold)
     All at idle:
     Startup current 0.16 A
     Current at 30 seconds 0.11 A
     Engine "warm" current 0.005 A
     Any more ideas???