5000TQ Avant Starting Problems

[Stephen Sherman]

Well, I thought this problem was fixed, until this AM.

I had tried lubing the previous starter, which helped a bit but didn't 
fix things, so I replaced the starter with a rebuilt. That helped quite 
a bit, and when comparing the old starter to the rebuilt, it was pretty 
clear that the old starter clutch shaft was very worn. Rebuilt sounded 
better too.

Anyhow all was well until this AM. It was cold again last night, around 
0F. Went to start the Avant this AM and all I could get was a click when 
the key was turned to the start position. Not the same problem as the 
old starter, it would not stay engaged in cold weather, but always spun 
when the key was on start. But perhaps related as both have issues with 
the starter solenoid when its very cold (around 0F). While it certainly 
could be this rebuild starter (can't assume they did a decent rebuild 
job), I am beginning to think the starter issues in the cold may be 
something else.

The battery is <2years old, and all connections to it are clean (checked 
that before). And the lights all seem bright so I don't think it is the 
battery failing in the cold. I was thinking that it might be an issue 
with the ignition switch and if it can pass enough current when its cold 
out. Is the starter "on" connection directly wired to the ignition 
switch, or is there a relay or the like somewhere in the circuit? Any 
history of how the ignition switches fail, is this the pattern?

Any other thoughts on what might be the real problem here?

TIA