My 2001 Jeep Cherokee Laredo's gauge spikes to the red and the dinging warning noise from dash goes off. But the Jeep is not over heating. I have no bubbling, No steam. no nothing. This happens when Im sitting still for about maybe 5 minutes. Then when I get going down the road the gauge goes back down to 220. What is going on????

 

there must be air in the line.

or your sensor is shorting out.

 

Thank you. I will have to check that.

 

U really need to verify temp with a infrared temp gun.

 

Good chance that it is a small pocket of air, either a small leak (cooling sys low) somewhere or a small amount of combustion gasses entering the cooling system, keep an eye on it.....
Good luck

 

overheating while sitting still, but temp dropping while moving =
bad fan clutch (much of the time). Make sure the belt is tight too.

While sitting still the cooling system relies on the fan to draw air
through the radiator, thus cooling the coolant (like that?lol). Then while
moving, air is force though by the forward movement and doesn't need
the fan as much.

 

check to see if the electric fan comes on if not there is a fan modual that goes bad .. and will do what u r saying let me know what u find out..

 

One thing to remember, with a 50/50 mix and a properly funtioning 15-16 lb rad cap, coolant will not boil/steam at 260F.....but 260F is definitely overheating.

 

This. Always best to verify.

If you find that the spikes are not real, the primary suspect would be a sending unit problem (or wire/connector).

If the temperature truly is creeping up at idle ONLY (not while driving down the highway), then the fan clutch is the #1 suspect.

You need to get under this and resolve it quickly. Any type of overheating is very hard on your cylinder head and if you still have the factory 0331 head on your engine, they have a nasty habit of cracking between cylinders 3-4, where there is a casting defect, upon any overheating.

 

try installing a new thermostat

 

Get yourself a real mechanical gauge and install it,Hesco sells a water neck with an extra port, you will be able to install the factory, and a aftermarket gauge all in one unit. Remember with an aftermarket gauge the more fittings used the less accurate your gauge will read.http://www.hesco.us/

 

Why? didn't you read the post?What's your reasoning for this?

 

Thank you so much everyone! Im a girl and I do not know much about vehicles

This site is a very big help. I am having someone put a thermostat sensor on today. I will keep you posted!

 

Mine just started that a couple days ago, when im driving its a cool temp but when i come to a stop the temp gauge rises way up, as soon as i take off it cools back down again. In october i installed a new water pump, t-stat, rad cap and hoses. So i should replace the fan cluch? Any certain cluch ? Or just a replacement one?

 

For the money and headache of cheap ones from the store's, I'd go with one from the dealer, if you dont want to go that way at least grab the best one out there.g/l Did you keep the spring in the lower rad hose? If not it is possible for it to collaspe,(it did come from the factory installed for a reason.)