[W126 Coupe] 89 560 sec with engine miss and rich, poor idle

[Rick Granlund]

HI-
	I don't mean to bother the list, but I have qa rather sever problem 
with my '89 SEC.  I tried earlier but did't get any takers in trying to 
diagnose the problem.  Hoping someone will chime in with the solution to 
my problem.
thanks in advance.
Here is the problem:
    The car
does not appear to have any enrichment when first started, but acts like
more than one injector is running wide open.  When it is first started,
cold, it will stall unless you give it enough gas (1000rpm or more.
After about 30 seconds you can let it try to find idle, but it hunts
between ~500rpm and ~800-900rpm or stalls.  The exhaust is VERY rich (it 
stinks
with fuel). I bought the car with a broken ( front vacuum
tube nipple)fuel pressure regulator and the idle was erratic and had 
bumped up to
1000 - to 1400 rpm isong the throttle linkage (the one link down under 
the front of
the throttle body, just behind the cruise linkage. It would still stall
and hunt up to 1400rpm. I replaced the fuel pressure regulator.....no
change!  So I replaced the Idle control valve....no change! I seems to
have a severe miss....running on seven, but it does that well above idle 
too.
   The miss is it running very 'rich'.  I replaced the distributor cap
and rotor and the plug wires thinking it was an electrical miss.....no
change. It appears just to be a very rich condition....all the time.  It
will not idle, just hunts 400 to ~900 rpm and stalls.  After stopping, 
it is very hard to start...like leaking injectors.
     I am thinking this rich condition is controlled by some electronics,
rather than a faulty injector....it just runs too rich.
     Could someone guide me through the logical troubleshooting steps to get
to the bottom of this problem? How do I check if the cold start injector 
is 'open' all the time.  Removing the electrical leads to it does nothing.
	I think if I can find the reason for the ery rich idle and run 
condition, it will solve the idle and 'miss' the car has at idle and in 
running.
Rick