What happens if your Thermostat is stuck open?
- Thread starter Kenny2g
- Start date
If the 'stat is stuck open then your car won't warm up to its proper operating temperature. This directly affects the heaitng system. Check your temp gauge when you drive - if it's hovering around the blue (ie: cold) area then it means it's stuffed. This is easy to fix yourself if you've got a spare hour or so.
And if your temperature gage is in the normal area, and your blowing cold air then it could be:
- a clogged/dirty heater core. To check this, try to locate the hoses going to the heater core. If one is cold, the return line, then the core is blocked. If both are hot then the core is OK.
- broken air divert assembly so outside air is blowing in, not passing thru the heater core.
- a clogged/dirty heater core. To check this, try to locate the hoses going to the heater core. If one is cold, the return line, then the core is blocked. If both are hot then the core is OK.
- broken air divert assembly so outside air is blowing in, not passing thru the heater core.
if your thermostat is stuck open the car will not heat up as quickly as normal and may not heat up as hot as it should because the radiator has to heat up with the engine.
If you are not getting any heat at all, you probably have other problems than your thermostat. If your temp guage is above the blue you should have some kind of warm air coming out of your vents. If not you heater core could be clogged or the linkage on the climate control.
If you are not getting any heat at all, you probably have other problems than your thermostat. If your temp guage is above the blue you should have some kind of warm air coming out of your vents. If not you heater core could be clogged or the linkage on the climate control.
The thermostat isn't the only thing that controls the heat. I would ofcourse change it if the temp gauge and to see if your temp gauge is ok, what u can do is when the thermostat warms up, you can pull the sensor plug on the block (it should be in the front of the block, under the intake manifold) and look at the temp gauge.....it should be dead center. IF it is, I would consider looking at the heater solenoid right next to the brak master cylinder mounted on the firewall. If the rubber rings are worn out in there, you will never get heat....take it from a guy that was in NYC last winter when it went out.
what if the heat you feel from the vents somewhat matches the temp. gauge, but the temp gauge keeps getting colder, then hotter, colder, etc. but never passes the half way mark? Even w/ a/c at full blast on the hottest day of summer (I tried) it did not pass the half way mark. Also, if I just let my car run without driving it, the temp gauge will come to normal operating temperature, but it starts to fluctuate when I drive it.
I'm thinking it's thermostat? Am I way off?
Sean
I'm thinking it's thermostat? Am I way off?
Sean
Looks like I'm going to have to change my thermostat also. Car is staying on the blue mark and blowing semi warm air. I haven't looked it up yet is it in a fairly easy location on our cars? Chesty mentioned taking an hour or so to change it out. that seems like a long time unless it's down low in the engine bay.
Oh man, I just found the tech article on Pelican parts site and they say to take off the belts, if I read it right the cylinder head??? the thermostat housing then pull out the old thermostat replace the o-ring and the seal. if you have corrosion then you need to use black silicone around the thermostat then replace everything in reverse order. I can't imagine doing all that in one hour. Chesty if you did that in an hour your the man.
Yeah your car might be different from mine (most likely) and all i had to do was take off the fan cowling and remove the manual fan. I had to get an open-ended spanner to get the fan off but once that was done the job was fairly easy.
It also helps that my dad is a mechanical engineer! LOL.
If you need a guide i wrote a big post about when i changed my thermostat. Just have a search around!
It also helps that my dad is a mechanical engineer! LOL.
If you need a guide i wrote a big post about when i changed my thermostat. Just have a search around!
Well the time here as i type this is 4:10pm.
The open-ended spanner is basically one that is only a few millimetres thick so that it'll fit between the fan and the front of the engine so that you can undo the nut. Remember that its a reverse thread! I'm not sure what car you've got but the 4-banger in mine was a little more difficult to work on in terms of removing the old thermostat.
Just make sure you check over things before you do it so that you have a fair idea of what you'll be doing. Once you've removed everything then it's pretty easy. Just make sure you put the gasket and thermostat housing on nice and even so the gasket isn't damaged when you screw it up tight. Also, make sure the new thermostat that you put in is up the right way. There will be an arrow in the leading edge of the 'stat and put it in so the arrow is facing upwards. Then you should be sweet! Let me know of any probs but i think i wrote pretty much everything in the thread u said u printed off.
Lastly, after you've put it all back again be prepared to let your car bleed the exceess air out of the cooling system for quite some time. When i did it i had to turn my car on and off for a good 1/2 hour before all the air was expelled. Then keep checking your radiator level for a good 2 weeks after - and don't forget to replenish the coolant!
Good luck.
The open-ended spanner is basically one that is only a few millimetres thick so that it'll fit between the fan and the front of the engine so that you can undo the nut. Remember that its a reverse thread! I'm not sure what car you've got but the 4-banger in mine was a little more difficult to work on in terms of removing the old thermostat.
Just make sure you check over things before you do it so that you have a fair idea of what you'll be doing. Once you've removed everything then it's pretty easy. Just make sure you put the gasket and thermostat housing on nice and even so the gasket isn't damaged when you screw it up tight. Also, make sure the new thermostat that you put in is up the right way. There will be an arrow in the leading edge of the 'stat and put it in so the arrow is facing upwards. Then you should be sweet! Let me know of any probs but i think i wrote pretty much everything in the thread u said u printed off.
Lastly, after you've put it all back again be prepared to let your car bleed the exceess air out of the cooling system for quite some time. When i did it i had to turn my car on and off for a good 1/2 hour before all the air was expelled. Then keep checking your radiator level for a good 2 weeks after - and don't forget to replenish the coolant!
Good luck.
Man, 4pm what a difference. Yes I will check on the air bubbles and leaks. By the way I drive a 93 325is. man it's nearly 11:30 and I have to get up early in the morning guess I'm logging off. Have a happy thanksgiving day tomarrow if you guys have that in Australia. I don't know what I am thinking you all don't have that sorry. It's a great Holiday anyway with all the great food you care to eat.
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This thread is too long. Change the thermostat and get it over with. Just make sure you put that ground wire back on the thermostat housing or you will start a new thread asking why #5 cylinder isn't firing and I will be the one to tell you that your just blew the ECU.
I do want you to keep this in mind though. The thermostat does not control the heat inside the car, the heater solenoid does. When that solenoid opens, it gets coolant flowing from the block into the heater core, hence you get heat. Now if the gauge is fluxuating that means you might have some air in your system and you need to bleed it out. I have a very good post on how to properly bleed your cooling system. do a search and I am sure you will run into it
I do want you to keep this in mind though. The thermostat does not control the heat inside the car, the heater solenoid does. When that solenoid opens, it gets coolant flowing from the block into the heater core, hence you get heat. Now if the gauge is fluxuating that means you might have some air in your system and you need to bleed it out. I have a very good post on how to properly bleed your cooling system. do a search and I am sure you will run into it