Gen 2, -F° rough idle, engine kills issue.

Hey all, new to this.

I have a 13’, 4.0/AC/4wd/automatic.
107k miles.

Bought it new. Had no issues until the last few years. Issue being at minus F° temps it’ll run rough or die. Hard for me to troubleshoot. I don’t always get minus temps and I travel a lot in the winter.

I have an arctic heater kit. Block heater/battery tender/tranny 50w heat pad/eng 50w heat pad. Also a second tank, gravity feed, and basically reads full all the time. Until I’m running only on the factory tank.

Doesn’t matter if plugged in or not. Heated garage or not. Usually only does it while stopped (stop sign/stop light). I can put it into N while stopped and rough run stops. Goes back to normal idle and it purrs. It’ll throw codes, O2 and rough idle. But is that the affect or the cause?

My old neighbor had the snap on scan tool, the big one. Tablet size. It read O2 sensors were on the path to fail. I replaced the O2 sensor, passenger side one, up stream. Plugs. (Factory plugs were two different styles‍♀️)

As far as I can see, smell, no exhaust leak. I don’t like the idea of throwing parts at it. But I also don’t have a ton of time to mess around.

I live in Alaska. So our temps vary a lot. My house can be 5F° and drive two miles away to the store and it’ll be -5F° and it’ll have the issue.

Plugged in or not. Ran long enough to push out warm air or not. It seems to really follow the temperature.

Any thoughts? Similar issues? Tips?
Thanks in advance.

 

I would still start with a few bottles of Heat or gas line antifreeze that contains methanol to remove any water to be sure. After that clean the MAF with CRC MAF spray and throttle body with CRC TB spray (2 pack at Wally World) or use brake or electronic cleaner in a pinch. Ever dumps any injector cleaner in (don't know what quality of gas you are using like well site stuff). Have you changed the spark plugs ever? Air cleaner OK? Does your temp gauge work OK (sensor) and thermostat working. Check vacuum hoses if leaking that drops the idle - big one in front of 4.0 by throttle body also that gets loose or cracked. Does it happen with defrost on as AC compressor runs so maybe that is failing and dragging idle down (turn off and see if helps or not). Any critters get up there - remove the plastic engine cover and look see if any wires chewed. Hard to find with no codes as you know. That's all I have this early.

 

Running rough when? At idle? All the time?

Try cleaning the throttle body