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Re: 5kcstq: Continued warm-up trouble

   I'm still having trouble with the car when it's cold. In the morning,
   after an overnight low of ~50 (just a guess), it starts just fine. It
   runs just fine for about one minute, and then starts stumbling. It often
   dies at this point, unless I modulate the gas pedal just right, and then
   it is very difficult to get it to start again. Sometimes it then
   backfires. After running for 15 minutes or so (well after the temp gauge
   shows plenty of warmth), it has gotten over it and it runs fine.

   This happens in the morning (55F, ~8-10 hrs after last running) but not
   when I'm driving home from work (70F, ~9 hrs after last running), when
   of course it's warmer outside. If I don't drive the car in the morning,
   though, it has the same trouble at night or whenever.

   This seems like a problem with the "warm-up enrichment" phase of the
   CIS, but I don't know what's causing it. At two listers' suggestion, I
   checked the fuel pump relay a la Bentley (which doesn't check the relay
   itself) and tried the output tests, and everything (including the
   frequency valve) clicked when it was supposed to.

   Anything else I can try, short of giving in and taking it to my
   mechanic? TIA.

Sounds like Control Pressure Regulator to me, or possibly the Aux
Air Valve (if so equipped, based on my '83 UrQ). Both are driven by
ign +12 to "warm up" and modulate the flow of extra gas (CPR) and
air (AAV) fed to a cold engine.

I assume you've monitored the Freq Valve (FV) to watch its duty cycle,
and it is not going haywire...

Hard-to-restart sounds like the Hot Start Pulse Relay (ooh ooh, a FLA,
HSPR) is not activating -- assuming the 5K has one...

					-RDH