doesn't like to stay running when cold

Ok, it has been as cold as -30C up here for a couple of weeks. I don't drive my jeep all that much (once per week or so) because it is a second (but very fun) vehicle. The last couple of times I have used it, the jeep doesn't like to stay running unless I stay on the gas a bit. If I let my foot off the gas it will slow down and then stall. I have to keep this up until the engine is warm, then everything is ok. I would have chalked it up to just being cold, but I didn't have this issue the last couple of winters. Any ideas?

Background info:
- '99
- 4.0L
- AX25
- fully charged red top optima battery
- cranks just fine, runs well once warm
- only issue is staying running after startup

just curious, what grade of gas is in it and how old?

I once filled up with 93 octane, just for a test to see how it ran :gee: . It happened to be winter, probally 15-20 degrees F :doh: . I had the same problem. I imagine old gas could also do this. Probally not your problem, but ...my 2 cents.

Hmmm.... good question. I guess the gas could be 6 weeks old now. I didn't think gas went skunky that quickly.

Anyone else have this issue with bad gas? Anything else that could cause this?

At first I thought I may have put the wrong viscosity oil in it, but 5-30 syn should be ok for cold temps.