Q-Jet Fast Idle Issues

[dz1087]

So back when the weather was Florida warm (80*+) in the morning, the truck had no issues at all and all worked as advertised -- press the gas pedal to set the choke, crank, fast idle, tap gas after a few seconds to take it out of fast idle, drive on your merry way.

Now with it getting in to the 60s and 50s in the mornings here, it is acting up a bit. It still sets fine and cranks fine. Still comes out after a tap on the pedal. However, now after coming out of fast idle, it places itself back in fast idle after I drive away. It will either stay in fast idle for about a mile, or if I stab the pedal come out of fast idle then go right back in, again for about a mile. Seems to not matter if I let it sit in fast idle for 10 seconds or 100 seconds after cranking either.

More annoying than anything, but it also doesn't seem to be the way it was designed either. Just wondering what I could do to fix it.

Truck is garage kept. Q-Jet had a complete rebuild accomplished by Q-Jet Power about 2200 miles ago. Using stock breather. Uses divorced choke.