Would loseing the coolant in my motor make my jeep idle rough and want to die at idle. it didn't over heat the temp. only went up 1 mark on the gauge. but there was a little smoke that came out when I popped the hood, it could of just been steam. Anyone have any ideas? I'm hopping all I have to do is change the freeze plugs. :confused:

If you have a head gasket that is leaking it will cause a rough idle.
do you see any external leaks?

Check the oil, look like milkshake???

Vacuum leak at the intake?

Leaking on or around the spark plugs or the wires?

If you have a head gasket that is leaking it will cause a rough idle.
do you see any external leaks?

Check the oil, look like milkshake???

Vacuum leak at the intake?

Leaking on or around the spark plugs or the wires?
The oil is fine, The only leak is the river thats flowing out of my freeze plugs.

There is no reason losing coolant through a freeze plug would affect the engine's performance in any way unless the coolant got low and the engine got hot.

First let me tell you that I'm no TJ expert. I have seen engine systems that have a computer requirement for a full water jacket. If the temp sensor is in a void, it will not sense an accurate operating temperature, or a high temp. If it is not at thermostat open temperature range, the sensor lies to the computer. The computer may operate in a closed loop or a warm up loop. This means a longer injector pulse and this is too rich for an engine that is actually warm or even hot. Now this creates a rich condition in the emission system which may lead to a rough idle.
I agree that a vacuum leak is a very probable cause. I torque my intake bolts every six months for that reason. I find the rear bolts loose that often. My idle suffers the effect.