This morning my engine was smoking. I looked under the hood and my engine coolant tank was shaking and boiling. My fan comes on a lot and the little lightning bolt comes on too. Any thought?

 

Mines been overheating lately. Not to the extent of yours like mine isn't boiling or I have no lights kicking on. Its going in the dealership on monday I'll let you what they find out. It might help you at least narrow down the problem.

 

I hope you mean your engine was steaming.

Does this happen on the highway, or around town?
Have you been in water deep enough to get mud/silt/debris in the radiator fins?
What is the engine temp gauge showing when this happens?
What's the water level in the bottle when it cools down?

 

Had the same problem about a month ago. Thought it was the water pump but turned out to be just the fins were clogged with mud. They had to pull the radiator and clean it so the air would flow thru.

 

Mines not steaming but I'll check my radiator out. Did you take yours to the dealership?

 

I noticed it when I parked. No I haven't been in any mud or water. My temp gauge was showing cold? So we replaced the thermostat last night and gonna replace PVC valve tonight. Any other thoughts?

 

Don't forget to see if your radiator cap needs replacing. Overtime they lose their ability to hold/keep pressure in the radiator...

 

Cap is good and so is pressure. Changed PCV and thermostat and sprayed off radiator but no luck.

 

first thing to ck is coolant level if its low , why? leak? coolant on ground ? ck your serpentine belt is it still there to drive the wAterpump? ck your oil appearance normal or milky which would indicate internal engine problems . most likely isa leak causing the smoke or vapor you saw resulting in low coolant . if the coolant was boiling you have lost pressure somewhere its impossible for it to boil if pressurized properly

 

You have symptoms of overheating, and your temp gauge was reading cold?

Sounds like the temp sender is reporting a false low temperature, which would keep the fan off.

Regarding the poster who said it's impossible for the water to boil if properly pressurized...
The water in some steam locomotives continues to boil into steam at 250 psi. The pressure in the JK's engine is only 18 psi.