I've had idling problems like this three times before. All three were due to air leaks that simply leaned the car out too much to idle.

1. The hose from the idle air motor to the throttle body had a split seam. This one got worse as the weather got colder. It was a fancy molded hose, so I used some oil resistant line and copper plumbing elbows to make a replacement.

2. Fat fingers knocked the flame trap out of place. Suddenly wouldn't idle.

3. After swapping engines, didn't tighten intercooler hoses enough, one popped off on the second drive.

Check for rips, tears, and missing parts in all of the intake plumbing. K-jet hates un-metered air. This may not be your problem, but it can be checked cheaply and easily...even with gloves on.