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!

 

[nuclearbunny911]

my 90 tsi awd started overheating the other day. i noticed my fan wasn't working, and i had to replace the relay switch. i also noticed a couple leaks in my coolant lines, replaced those and everything worked fine, but earlier today was driving around when suddenly it started overheating again. i had to stop 4 times on the way home to let it cool down. it seems that when it's overheating, it sometimes suddenly starts to cool off, then just as quickly heats back up to the red, but whenever i pulled over, it seemed to cool down on the turn as i breaked, then heat back up again.

i'm thinking my water pump could be bad, any suggestions?

 

[romeen]

Your thermostat could be getting stuck. I would try replacing that first.

Usually when a water pump is about to fail it will start leaking coolant. You will see puddles under the timing belt cover after the car has been parked for awhile.

 

[Pat D]

Double check your fans are turning on. If there not it could be the fan switch next to the lower radiator hose...Also I would pressure test your system for leaks..

 

[roni-wan]

Check your thermostat, also for worn or too old water hoses, fans, radiator cap or maybe a coolant leak.

I had some ramdom overheating problem the problem was some old hoses.

 

[phastalon]

Okay my 1g awd auto is overheating and I can't pinpoint why. Here is what I have found so far:

The water pump is working.
Fans won't come on, even after unplugging coolant temp sensor.
Coolant temp gauge was reading hot, then read normal temps after I unplugged it and plugged back in (even when car was HOT).
Took car for quick run around block and temp gauge read HOT, but cooled down under boost, then went HOT when I let off gas.

Possible fixes (in order of cheapest to most expensive, haha)...

1.Fan relay
2.Thermostat
3.Radiator Cap
4.Coolant temp sensor
5.????

Thanks in advance for the help.

 

[luv2rallye]

Coolant temp sensor must be working for ECU to turn fans on - check it first. Around 2 ohms @ 68F (296 ohms @ 176F).

 

[Pat D]

We had the same problem with the temp senser and we replaced it with a Napa one and it didnt work very well either so we went back to a OEM one and problem solved.

 

[phastalon]

So you guys seem to think it's the coolant temp sensor. Would a bad sensor cause the car to overheat?

.....(my theory)....if the temp sensor isn't working, the fans won't kick on, causing overheating. Am I close?

 

[freshlane]

install a jumper wire on the fan relay to keep the fans on (it should work)and drive around the block. The reason it might be overheating under boost is because the car has enough air being forced through the fins (kind of like highway driving). I drew a diagram (it is looked at as if you are standing in front of your car). It should keep your fans on once the key is in the ON position. Post back with results. If it works then it may be your relay is bad

You must be logged in to view this image or video.

 

[9TalonNT6]

My 90 Gst only doesnt turn on my cooling fan the only fan i can get to run is the AC fan, can anyone guide me as in what to check? I changed the radiator fan relay in the engine bay still nothing.

 

[teamitr]

Have you checked the actual fan to see if it's working?

 

[luv2rallye]

Check your engine coolant temp sensor (not the one for the temp gauge). Also leaking ECU capacitors.

 

[DSMULATOR]

Turn the A/C on and disconnect the harness to the fan that isn't working. Test it with a test light to see if its getting power. If so, you know the electronics are working and then you can jump the fan motor to see if that's the problem. If you've got no power, then you have to start chasing the circuit for bad sensors, broken wires, shorts to ground, etc...

 

[Evo_KLR]

Hey guys, just joined this site and I love it.
Anyways, I drive a '90 plymouth laser rs turbo.
Recently, me and my buddy installed a FMIC.
Well, since the install; my car has been over heating I believe. And also my "check engine" light comes on if I drive it for too long.
The coolant under my radiator cap is boiling(yes, I can hear it bubbling) to the point where steam is coming out of it.
We tried everything we could think of... I bought a new radiator, took out the thermostat because we thought it wasn't working; we are running out of ideas as far as "easy fixes" go.
I ride around with the a/c controlled fan on all the time, and it still boils.
I only have that one fan on right now because I haven't gotten the chance to buy a slim fan yet, but could ONE more fan really prevent boiling?
Any ideas?!
My mods are simple and include MBC, 3" downpipe with o2 dump, and a couple small other things.
Thanks in advance guys!

 

[daves06r1]

your fmic could be blocking air flow to the rad and the second fan isnt a bad idea to get back in there.

 

[drewvr4]

i am having the same problem except mine has been an ongoing thing...

first off when your car is hot, is the lower hose hot as well?

 

[LambdaJoker]

sorry for bringing up an old thread, but i have a question.

i have a brand new cometic head gasket on my car and the water boils when i boost? does that mean the hg is bad???

 

[Evo_KLR]

Both of my hoses are blazing man.


So my FMIC might be blocking air flow?
If that's the case, what do I need to do to get it cooler AND keep the FMIC?

 

[HonduhKillaTSi]

Your FMIC shouldn't be making you overheat that badly. Have you replaced your water pump yet because that would probably be my guess. You say you ride with A/C fan on also, hopefully you have no A/C belt on it because the a/c puts more strain on the motor and makes it run a lil' hotter. Try replacing your coolant temp sensors too, that wouldn't hurt. Do a coolant system flush too, something could be blocked up.

 

[BUCK]

Within all likelihood yes - MANY Threads on this especially if one were to query Cometic.

 

[Pat D]

Your FMIC shouldn't be making you overheat that badly. Have you replaced your water pump yet because that would probably be my guess. You say you ride with A/C fan on also, hopefully you have no A/C belt on it because the a/c puts more strain on the motor and makes it run a lil' hotter. Try replacing your coolant temp sensors too, that wouldn't hurt. Do a coolant system flush too, something could be blocked up.

On VFAQ there is a trick that you pull the A/C relay and your A/C button turns just your fan on and not your compressor. Get the other slim fan your FMIC might be too thick and needs two fans

 

[snox135]

also check and see if your radiator cap is good boil some water stick that sucker in and see if it opens.

A radiator cap opens with pressure not temperature. A themostat opens at a temperature.

 

[Evo_KLR]

Ok I'll try that tomorrow guys.
But yeah, I don't have an A/C belt on my car.
Anyways, Ill let you guys know if it worked.
Thanks!

 

[Talonman86096]

Just to make sure have you checked the one fan you do have to make sure it is working properly?

 

[krummel45]

I have searched the forums and have not found any thing simular to this problem

Here it is;
I was driving at around 20 mph when smoke started to come from the hood, so I stoped and looked and saw that the hose that went from the bottom of the overflow tank to the radiator cap had a hole, I rplaced the hose filled the car back up with coolent let the air excape. I thought the problem was fixed because I drove down for about 3 hrs at 70 mph with no problems even had a/c on .

The next morning I started to drive the car in the city and I am in FL, when the a/c was on the gauge started to show over heating so i turned on the heat and droped the temp down and then turned the air/heat off, no more problems. However about an hour latter I was sitting at a stoplight and it started to over heat agin so I turned on the heat and it dropped it to about 3/4 and when i started to drive from the stopp light it droped back to normal however when I stopped at the next stop light it happened again.


The coolent is 50/50 mix the main fan turns on when the car starts and the a/c fan is turning on when the ac is on. If i do turn the a/c on the car will start to over heat.

So what I do know is:

Coolent mix is good
The hoses are good
The cap is good
No air in the system

What should i do?

Thanks