Ruh Ro Shaggy!!

This morning I went to warm up my 2000 9-5 2.3t and it would not stay idling unless I kept my foot on the gas, keeping RPM at around 1200 rpm.
Temps were below 20F (16 to be exact) so I attributed it to that. Although I hadn't had this problem before with temps this low.
Once I got it idling, I noticed the CEL on. Plugged in the OBDII reader and got these codes:
P1263
P1231
P1230
In that order.
From what I've read, the P1263 references the throttle body. The others I can't seem to find. (I'll check the WIS when I get home)
As a test, I got on a back road and came to a stop. Idle was rough, but remained running. When I began to accelerate I noticed sluggishness so slowed to a stop.
Then I "mashed" the pedal to the floor and the car died. I've had this happen before and is the result of the throttle body going into limp mode. (I'll reset that when I get a break at work.)
The funny thing is that my "limp mode" doesn't present itself as others have described. I can drive the car just fine. As long as I don't push the throttle to max.

So I guess my questions are:
1) Are all the codes related to the throttle body problem?
2) Is there something else I should investigate?
3) Does a thorough cleaning of the TB essentially "cure" these problems?

Why do these things happen during the "worst" weather conditions? (I hate the cold -- lol)

Thanks in advance guys and gals.

- Mike