The coolant temperature in my car is still not right. The car will warm up to normal temperature (about half way up the stock gauge) and stay there for a while. Then it will randomly warm up to about 3/4 of the gauge and the fan will kick on and push it down to normal. It will stay there for a while and then it will warm back up. I figured I had air in the system, so I took off the cap above the thermostat housing and let it run for a while, because I remembered reading somewhere that I could burp the air out that way. I walked away from the car to go get some butt connectors to hook up my stereo, and when I cam back the car was about to overheat! The thermostat housing was running over with coolant. So I shut the car off and let it cool down.

After about an hour, I ran the car to see if it would overheat on me, cause I have class in 3 hours and it's my only car now since my mom's mustang has a fuel problem at the moment. It doesn't overheat, but it still has the original problem with the heat going up and the fan cooling it down.

Anyone have suggestions as to what my problem might be. Was my method for burping the coolant correct? If not, is my thermostat messed up, or should I be looking at something else?

T-stat or Coolant Temp Sensor might be your issue. T-stat might not be opening all the way, or the CTS may be failing and not kicking on the fans early enough.

Is there a way to test either without just buying a new thermostat. I'm close to broke and I don't get paid till tomorrow, so I'd rather figure out what it is and spend the money just the parts I need.

CTS can be tested with a multimeter for resistance at temp. T-stat you can pull it out and throw it in a pot of boiling water to see if it opens up all the way.

What Ronin was saying might be the problem, but you might have a restriction in the cooling system. Have you ever flushed your radiator?

You should check your coolant temp sensors first. The sensor for the gauge should be 9-ll kohms at 77 degree F.
The small sensor with a one pin connector should be 104 ohms +/- 13.5 at 158 degrees F.

Hope it helps.

EDIT: Have you ever replaced your thermostat?

ez's right. http://www.2gnt.com/index.php?d=CLT

you can get a superstat, guaranteed to never go bad for like $15. Advanced/autozone really stand behind on it too as long as you keep your reciept. I've had one go bad, and they gave me a new one, no questions aasked.

While you're doing this, flush/fill ur system too.

Originally posted by 420agreenvilleSC
ez's right.

since when did I become ez? :scratch

+1 on the coolant temp sensor. Are your fans coming on?

I have no ac, so I only have one fan but it does come on, radiator is brand new. I put it in like 3 weeks ago. The fan is actually what is pushing the temp back down. It heats up and then the fan kicks on and cools it back down. So far it hasn't overheated, but with the temperature going up and down so fast, I'm scared something is going to f up on me.

I'll have to ask around and see if I can get a hold of a multimeter. I get paid tomorrow, so I'll grab a new thermostat after I cash my check. I've replaced it before, but the car sat for almost 2 years after, so It may very well be bad now.

If it's the sensor, I have a parts car in the works, but I need to get the time to pick it up. I'm studying for my Network + certification exam and my CIW exam right now. Both are on Monday morning and I have a couple hundred pages to read before so the car is on the back burner for the moment.

(edit) Thanks for all the suggestions guys, it's very appreciated.

Hmmm, you may have pulled the wrong fan.