Thermostat Problems

[95Vert]

Why does my thermostat wait until my car is literaly overheated until it opens. I can smell the fumes inside the car. This is my second 180* thermo that does the same thing. Do you guys have any idea? Should I go back to the 196*,but won't it be worse since it's a higher degree?
Thanks

 

[Swarzkopf]

I think you're cooling system has other issues bro...is your cooling fan working? How's your radiator look?

I'd think that you thermostat is opening at 180 and that your car is overheating due to some other issue. Perhaps the cooling fan isn't coming on until too late?

My car was having similar issues a few months ago. I first installed a 160* T-stat and flushed the cooling system. I was still having issues. On a Stangnet members advice I replaced the ECT sensor for $20 and my problems went away. Now my car runs cool as a cucumber all the time.

 

[CManT1914]

Yea if your car is overheating, I doubt it's the t-stat. More likely a bigger issue, like a fan, clogged radiator, faulty ECT (seems to be a common problem). Have you pulled the codes? A bad ECT will give a code out, even if the CEL doesn't come on.

 

[WhiteDevil]

yeah odds of two thermostats in a row being bad is pretty slim

 

[94opalgt]

stupid question,but what the hell is a ect sensor?is it the sensor on the front driver side of the motor?i cant remember if its actually in the block or in the timing cover.

 

[CManT1914]

stupid question,but what the hell is a ect sensor?is it the sensor on the front driver side of the motor?i cant remember if its actually in the block or in the timing cover.

Engine Coolant Temperature sensor. It's located on the end of one of the heater core lines at the front of the motor, right to the left of the distributor.

 

[BPA]

Electronic coolant temp sensor..ect... if you really believe it isnt opening use temp gauge to mesure before and after the thermostat at the housing.

 

[Swarzkopf]

Engine Coolant Temperature sensor. It's located on the end of one of the heater core lines at the front of the motor, right to the left of the distributor.

Exactly. It sits on the top, front, passenger side corner of the lower intake manifold, at the heater core lines just as CMan said.

 

[DarkProphet]

Or, if your Tstat is in backwards it could do that... Doubt you did that though

 

[madams74]

Best thing to do is to take out the T-stat get a pot of water. Get a thermometer capable of 200+ degrees and boil it to watch when it pops open. I would suggest just buying a good t-stat. Not a cheap Stant. Mr Gasket is good. I would just replace the sensor also. The sensor is over a decade old most likely. It has been getting hot and cold for this many years and is most likely fouled. I believe in a PM for any engine over 10 years old. This means belts, plugs, wires, distributor cap & rotor, coolant flush using strong acid based additive, and any sensor that is plugged directly into the block or exhaust. Those 02 sensors are very bad about causing problems.

 

[HISSIN50]

Yep, more info on when it runs hot and what leads up to this would help.

Good luck.

 

[95Vert]

Nope, I didn't install my thermo backwards. Just to be a lil more specific, it does it in the mornings. I go and start it and drive it for about 7-10minutes and the temp climbs all the way to the H, and as soon as I can smell the antifreeze, it opens and it goes all the way down to the O. After that, it'll run fine all day long without even getting close to the M. Today, it completley overheated. I let it sit at work for about 6 hours and on my way home, it was way up there. It took about 10min for it to open up and then it ran fine. I took it off as soon as I got home. I just drove it for about 10 min, and it was at the R, without going any higher. Ya'll still think it's the ECT? The fan is coming on fine as well. The car was parked for about 2 months, you think that had something to do with it?

 

[Swarzkopf]

I'm assuming that this happens while moving at speed and while stopped?

****, sounds just like a bad thermostat.

 

[95Vert]

I'm assuming that this happens while moving at speed and while stopped?

****, sounds just like a bad thermostat.

You're right. I don't know if I should still switch out the ECT tho?

 

[Swarzkopf]

You should follow the instructions for testing the thermostat posted here: Boil a pot of water with the T-stat in it, and record the temperature at which is opens.

 

[HISSIN50]

You're right. I don't know if I should still switch out the ECT tho?

If the LS fan comes on at ~208, that suggests the ECT is calibrated at that temp at least (which is very close to your t-stat opening temp). The ECT has a thermistor. You can check the values to see if it is within spec.

good luck.

 

[18mustangs]

It sounds like air in the cooling system to me. Perhaps you should try to burp the system and see if it goes away.
TIM