[s-cars] Stumble and miss when cold, really cold. NOT POS

[James Shackelford]

I have had a problem with my 93 S4 missing VERY badly when cold.  It doesn't
happen in the summer months, only when the temperature drops.  If I let the
car warm up until the water temp is at fully operational temperature, it
doesn't miss.  That is, the engine compartment and engine are at operating
temperatures.  It doesn't seem to miss as bad over 3K RPM either.  Any
ideas, I was thinking coil perhaps.  I thought maybe the fuel pump, but it
isn't affected by temp because it's in the trunk.  Is there any electronic
piece in the engine compartment that controls fuel?  The stumbling is VERY
bad, something that I don't think loosing a single coil would cause, unless
of course it's two.

Things I have done.

I have tested with two known good POS's with no change in behavior.

Wouldn't mind testing with someone's coil pack, though I would have to do it
at my house, cause if I drive somewhere else, it will be warm by the time I
get there and be done for the day.  Just using the whole coil top plate for
ten minutes would eliminate or confirm the coils.

I am in Littleton CO, any takers.  Brian P?

Thanks,

James Shackelford