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Discussion Starter · #1 ·
So my car overheats after 5 minutes of any kind of driving.

I cant find any leaks, water pump and thermostat are new. I flushed it today, nothing. I bled it 5 times, and it still keeps doing it.

What else could make it overheat so quickly? I dont think the hg is blown, no water in the oil, oil in the water, and it has pretty good power still.

I cant think of anything else.

Any ideaS?
 

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maybe there's still air in the system. it can be a bitch to get it all out.

run the car with the rad cap off and watch for bubbles.
 

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Discussion Starter · #3 ·
What can I do to make sure I get all the air out? The bleeder screw on the water cock broke off, so Ive just been disconnecting the little hose next to the upper rad hose (I guess it goes to the throttle body or something? Intake mani maybe?) and filling it up till water comes out of there.

Thats what my mechanic friend told me to do. Is there a better way w/o using the bleeder screw?

thanks for the reply
 

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Blast your heater also when bleeding the system. If you think you got it all out and it still over heats, it's probably your thermostat is stuck closed.
 

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i'd run the car without the radiator cap on. and keep filling up the radiator with coolant until no more bubbles come out. imo its the best way to do it.

some people have driven around with the cap on after adding coolant, then quickly popping the hood and opening the radiator with a beach towel and all the air came out that way too.

1st way is much safer.
 

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I once replaced a thermostat.. And I got a bad one...
There for I had to replace it again...

I would open the radiator cap, and squeeze the bottom house a couple times
This will create suction and help take air out.

Allow the car to run with the cap off for a little... And keep filling it up.
 

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is the car actually over heating or is it just the gauge that says so?

take the temp sending unit out place it in a pot and heat the water up. note the resistance at the 2 terminals as the water heats up.
i dont remeber exactly what the resistance should be but the fsm should have it.

thats the fuel injector temp sensor the one to the right of it is the gauge temp.
if u have any acesss to a gauge tester then id recomend testing it cause when i did mine the gauge wasnt reading anywhere close to what it should be.
 

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Discussion Starter · #8 ·
The coolant temp guage stays planted at the middle. I mean overheating by OMG I cant see cause there is too much steam. Well, not that bad but you get the point.

If the thermo was stuck closed, the top hose would stay cold, right? Its hot...and I can feel it heat up when the guage rises.

Im going to replace the cap and the tstat now, Ill see what happens.
 

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Discussion Starter · #9 ·
Well that didnt fix it.

You guys are saying to take off the cap and let it run to get the air out, right? Well when I do that, it runs for a bit, heats up, the thermostat opens and it lets a few bubbles out. Before all the bubbles can get out, it starts to boil and then I get all sorts of steam coming out of the cap. Is that supposed to happen?
 

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o well then
my next guess would be a hair line crack in the head gasket so that when the cylinder fires exhaust is pushed threw the leak and into the coolant causing the system to fill with airbubbles
 

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I thought if you had a blown headgasket, then the cooling system would be pressurized and it would shoot the water out of the radiator when the cap was off. Is this true?
 

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Td5turbo said:
I thought if you had a blown headgasket, then the cooling system would be pressurized and it would shoot the water out of the radiator when the cap was off. Is this true?
Yes, this is true.
 

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After 5min of driving that heats up pretty dam fast if you have no leaks and the temp should go down while your driving even if its overheating sounds like to me you could have a bad TEMPERATURE SENDING UNIT check that out its a little sensor thats say how hot the car is running its a cheap fix also and another thing is take the radiator cap off and start the engine if you have a volcano of antifreeze you have a blown headgasket, check under the radiator cap for any white residue also signs of a blown headgasket
 

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Td5turbo said:
I thought if you had a blown headgasket, then the cooling system would be pressurized and it would shoot the water out of the radiator when the cap was off. Is this true?
it will do that if you take the cap off when it's hot.
if it's the head gasket you will see bubbles or it will be frothy when you idle the car with the cap off.

did you also check the oil? if there's coolant in the oil, or oil in the coolant it is definately the head gasket.

when you run the car do both the top and bottom hoses get hot? if not it could be a flow issue with the radiator or the thermostat not opening.

if the water pump or clutch fan are working, but not to spec, they could also be the culprit.
 

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I`ve had experiences that lead me to believe the method of turning the car on and checking to see if water jumps out of the radiator with the cap off is an accurate way to make sure the headgasket is intact.

Yes, he`s checked for water in the oil and oil in the water.
 

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Discussion Starter · #19 ·
oh, well in that case its probably a head gasket.

if i start the car up with the rad cap off my entire driveway gets wet. lol. i thought that was just the waterpump spinning up though. it doesnt shoot too much out after its idling. but I guess it wasnt actually boiling right away, maybe thats just exhaust gas coming out of the cap?

and i got it to stop overheating i think, but when i turn the car off i still hear some bubbles.

I guess Ill try a compression test tomorrow and see how it goes :(
 
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