Temp Gauge all over the place need Help!

[zoomzoomMSP]

Ok so i thought i had this issue figured out but im still experiancing the same problem. Car was running fine and then i noticed a small coolant leak so i replace the upper radiator hose. after installation the temp gauge would pin to the hottest point and stay there for a few minutes and then would return to normal running temps and then back to high and then back to normal. car runs fine and has no other apparent issues other than this. oh one other thing actually. the fan has kicked on a about a minute after i shut the car off which its never done before..... ive also only owned the car for about 2500 miles. (car has 51000 on it now) so something it up.... i was told i have air in the lines since i replaced the hose and was told to remove the Rad. cap and let the car idle and the air bubbles should vent out and that this would solve the problem so i did. still have the problem, i let the car idle for about 5 min. do i need to let it sit longer is there another technique?
my other thought is that having air in the lines is not the problem, does anyone know what would cause the temp gauge to go crazy? any help would be great guys, id really like to figure this out. no CEL or any other lights. thanks

 

[USAFVMI08]

Your thermostat might be going bad. Try replacing that. They're not too expensive.

 

[zoomzoomMSP]

thermostat, ok... were is it located? is it something i can replace my self? anybody know a good place to buy one? is it something i can get at any autoparts store?

 

[USAFVMI08]

It's on your engine block where the upper radiator hose connects. You can try an autopart store. They may have to order one for you but I guarantee it'll be cheaper to do that than to go to the dealer and get one there

 

[zoomzoomMSP]

yeah dealerships are a joke when it comes to ordering parts. looks like ill be getting one through protege garage. i hope this fixes it. thanks man.

 

[KrGsMrNKusinagi]

Mine did it when I first got it.. I had air in the lines. The heater would work and not work as well. I had to basically pop the cap off the radiator and let it sit and rev a little till the air escaped. It has Never done it again since then.

 

[SteveJ]

I suggest that if you try burping the cooling system, park with the front end higher. That will allow the air to escape better.

 

[Coaststarlight]

Thermostat, My temp gauge did nothing, and even gave a cold reading, just lost power and died one day, and thats how this happened:

http://www.moccforums.com/forums/index.php/topic,22597.0.html

 

[nardvark]

When you're purging air from the system, you need to let it run hot enough to open kick the fans on and circulate fluid through the entire system. You will need to sit there with your foot on the gas, running it at 3,000 rpm or so, if you want it to heat up enough in 5 minutes to kick the fans on. It also helps to have the front of the car elevated for this, to make it easier for the bubbles to move up to the open radiator cap.

 

[zoomzoomMSP]

so i followed all the suggestions and its good to go now. no money invested to fix the problem, thanks guys!!!

 

[nardvark]

Hey, good to hear. Kind of hard to believe air bubbles can get stuck like that for so long, but they can!

 

[KrGsMrNKusinagi]

so i followed all the suggestions and its good to go now. no money invested to fix the problem, thanks guys!!!

Congrats.. Yea I had the same problem scared me at first till I realized what it was.. Temp said H but the radiator ws cold..Popped the cap let it run for awhile held the revs around 2,500-3,000 the airbubbles finally came out and the fluid level dropped then refilled it. All is well now