Someone please help me

[ChrisJeep]

I hope I'm in the right area to post this. I apologize if not.

I have a 2002 jeep liberty 3.7l (4wd for u AutoZone workers ) the gauge on the dash for coolant temp is reading half but the vehicle is boiling in the reservoir. I replaced the temp sensor on top and still doesn't read overheating and is still overheating. I flushed the system 6 months ago, it has Hoat coolant in it, I reburped the system to no avail. Going to try the thermostat next but typically that doesn't make the gauge read wrong from what I understand so is it even worth it or should I go straight for the heads?

 

[KJowner]

Boiling or bubbling? Get a garage to test it, they can see if combustion gasses are in the coolant.

 

[ChrisJeep]

Boiling or bubbling? Get a garage to test it, they can see if combustion gasses are in the coolant.

Oh its definitely boiling hot lol but I suppose it right, could be bubbling as well. It started misfiring too so more than likely the head. Thank you though.

 

[Hec In Omaha]

Faulty radiator cap can cause this too. Replace the cap if it’s older than 5 yrs old.

 

[duderz7]

I agree with the above. If the cap isn't holding pressure coolant will boil at or below operating temp. Water under pressure has a higher boiler point.

 

[DadOSix]

Dash gauge lies. It is no-where near accurate.

Follow KJOwner’s post and get it checked for combustion gas in the coolant reservoir. A Head gasket failure can put combustion gas in the cooling space. Can alternately allow coolant into the engine, and into the crankcase. Pull your dipstick and see if it is normal, or chocolate looking.

Slight possibility it is the water pump, but with the addition of misfires, i think you have at least a head gasket issue or a bad head.