Car Overheated / Overheating / Overheats [MERGED]

[NTRCOOL]

OVERHEATING? The issues and their solutions have remained the same- either you don't have enough cool air reaching the rad, there's a cooling system obstruction which is preventing coolant from circulating, or your head gasket has failed and is allowing coolant to be consumed or pushed away from the engine.

Discuss all possible overheating problems and solutions here.


OK,
I just left my house to go over to my GF's,and happen to look down and see my needle right before the red mark. This just happened out of nowhere. I stop the car as quickly as i can, and pour in some coolant(Coolant a little low). Still same thing. Welp im in the middle of the road, and HAD to get it home. Im only 5 min from my house. I decided to try and make it(I really had no other choice). Welp I drive no faster than 20mph, and the temp needle is BARELY into the red the whole way.And occasionaly to the left of it. Am I ok?? Do ya think any damage was done?? And im thinking either thermostat, or water pump. For each of those, whats a round about $$ figure to get replaced?? Any info you have would be GREATLY appreciated!

 

[darkrage]

As stated - the engine temp meter was all the way hot right before I shut it off... BIG puff of steam when I opened the hood and it looks like coolant is boiling out? dont know but its funky.... I dont want to drive it cuz it overheats like a bish... whats the problem?

 

[hdswanny]

its prolly the thermostat, change it and see what happens. it'll prolly cost about $5.

 

[darkrage]

probably bad installation, my friend put in this one and thats when I started.. arrgh

 

[zadir]

Check all your hoses, turn the car on let it idle then open the throttle and rev it a little keeping an eye on all your hoses near your thermostat housing. This is how I found my leak which cause that to happen....

 

[darkrage]

found it - bad gasket - it was shattered

 

[zadir]

Just curious, which gasket?

 

[nutshot]

How much coolant did you lose? Was there water in the oil? Where the plugs brown?

 

[alwaysworking]

Also, check your oil level. Sometimes low oil can make the car work too hard. And also check you fans to make sure they are working. My fans broke down and only allowed my car to go short trips before the temp. got to high.

 

[pilsner]

so here's what happened: i was driving on the highway today, just sitting in fifth gear on cruise control, doing a steady 110km/h up and down some mediocre hills, without pushing my car hard at all. barely even touching boost. so after about half an hour of this, i look down to see my temp gauge about 3/4 up, and then proceed to go all the way up to the red zone. i pull over and there's steam shooting from the overflow tank's overflow tube. there is practically no coolant left in my system. this has happened a couple of times, but i went through different tests and thought i had fixed it. here's everything that's been taken care of: new rad cap, new thermostat, cleaned all of the debris out of the fins of the rad for better air flow, checked flow of coolant for possible water pump failure, checked how well fans turn on, checked for blown head gasket, there are no leaks in the system (had pressure test done). i don't know what else it could be. if it is the coolant sensor, how would i test for that? could somebody please help me figure this out?

 

[Blocordi]

If it only happens on the highway it could be a partially blocked core. You will still see water flow if you look in the radiator once the thermostat is open, but with the slightly higher revs of highway driving with less available radiator to go through the water isn't in the radiator long enough to shed its heat before it goes back into the engine.
If the overflow hose and the radiator hose is revearsed on your expansion bottle you radiator will lose water that way.

 

[Blocordi]

When you say coolant sensor do you mean the sensor that turns on your fans? If so it is eralavent on the highway becaus of the airflow through the radiator at higher speeds.

 

[Blocordi]

Just posting as I think of things. If you are talking about your fan not running just run a wire from the 12v to the output of the control relay and the fan should fire up. Then take it for a spin and see what happens.

 

[pilsner]

thanks for the quick reply, but the revs weren't that high; only at about three or three and a half thousand. and yes, i did mean the sensor that turns on the fans.

 

[Blocordi]

I have seen a water pump lose effecientcy because the water had lots of minerals in it and over time the blades had been corroded.

 

[Blocordi]

To check the sensor pull it out of the radiator and boil it. You'll need an ohm meter to check its resistance. As the temperature rises the resistance should drop to nearly nothing. when it cools off it should be quite high.

 

[Blocordi]

Though of someting else. If the sensor is ok the fan switching relay might be dud. On my Mitsubish all the control relays are the same so you can swap them to see if one has failed.

 

[pilsner]

hooking the car up to a diagnostic computer wouldn't reveal a faulty sensor, would it? also, my rad light has been on ever since i got the car, and neither i nor my mechanic can figure out how to turn it off. how soft would the hoses have to feel to know they need replacing? thank you for all help.

 

[pilsner]

oh, yeah, when this first started i went through all of the relays on the fans and nothing came up; they work fine.

 

[heavenlyone]

i dont know but when ur driving at high speeds shouldnt ur temp be cooler? or is my car wierd =P

 

[pilsner]

i found out some more about this problem. i had the fan sensor replaced, so it's not that. got a new rad cap as it was only holding 7lbs. then i took a road trip, and this is what happened. my temp gauge reads normal, with slight, barely noticable changes. however, during this time the coolant is being pushed out to the overflow tank and then out of that. what was weird was that i drove, everything seemed normal, and then i stopped for gas. i let my car run for about half a minute before filling up, and i hadn't been driving hard at all. the highway was fairly flat, and i wasn't pushing hard at all. anyways, when i restarted my car, the temp gauge was immediately at 3/4. i just don't get it. i even had it a mechanic who thought that the new fan sensor had fixed it. the only thought i can come up with is that my water pump is somehow intermittant, however that might happen. any suggestions???

 

[boosted_91_tsi]

Could it be a kinked hose somewhere.....or a busted heater core, check to see if your heat is blowing out hot air.

 

[Blocordi]

Did the temp stay a 3/4 or go down? The water sitting in the engine after shutdown soaks up the heat so if you stop for about five minutes the temp will read high when you start up. On the highway five minutes of driving should return it to normal if everything is working as it should. You may have a sticky thermostat. I always boil my new ones to make sure it works before I install it. I've been caught before.

 

[91eagle_tsi_awd]

theres 2 sensors on the radiator ,check both of them out,samething happend to a friend of mine

 

[pilsner]

my heat always blows hot air, and the reason that i mentioned that my gauge was at 3/4 was because i had never seen that before. i don't know if it dropped or not, because i didn't give it the chance to; i just pulled into a parking spot and let it cool down, and then topped up the coolant. i don't think that it's the 'stat, because if i start my car cold with the rad cap off, i can see the fluid at a standstill, and then after a few minutes, as the temp gauge in the car goes up, the fluid starts to move. the fans do kick on and off shortly afterwards as well. as for the 2 sensors, i only know of the one at the bottom; where is the other one? what i don't understand is that the overheating problem only arises when most of the coolant is missing; where does it go? a pressure test was done on the system and it came up fine, so it must go out the rad cap, right? or is there some other way? i drove around town yesterday, and my temp gauge was fine all day. after i let the car cool down, i took off the rad cap, and guess what? i had to refill about 2 litres of coolant. is it possible that something is causing my car to overheat without affecting my temp gauge? if it is just the high temps and nothing else, then what would my gauge read when the heat is causing enough pressure to exceed that of the rad cap? i've been trying to figure out what would cause enough pressure in the system without creating heat, and the only things that i could come up with are collapsing hoses and a blocked heater core. (the rad's not blocked, it was removed and cleaned) but it seems that i don't lose any coolant when it's idling, so that should point to collapsing hoses at 3000 rpm, right? the engine was rebuilt before i bought it, and i came to thinking that maybe somehow the shop screwed up, but i don't know what would have to go wrong during rebuild to cause this problem? thank you very much for all the responses, and any more suggestions are greatly appreciated. if my logic is wrong, please tell me, i am completely lost right now.

 

[Blocordi]

I once had a turbo water return pipe that haden't quit sealed onto the turbo. It only leaked once there was a little pressure in the system. If the hoses are collapsing, it will do it in your garage if you grab onto the throttle and bring the revs up and hold them for a few seconds. The radiator cap is designed to let out some water into the expansion bottle as it heats up. As the water cools off and the pressure drops the radiator should draw the water back in.