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Engine Coolant HOT

Messages
153
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102
Location
Woodbridge, VA, USA
#1
Been having some troubles in these hot months.. a few weeks ago my car overheated to the point of dinging at me and the temp all the way up (AP not connected at the time) so I cranked the heat and rolled windows down and it cooled down. Next day it keeps getting really hot really quick so I check the coolant and it was low, I topped it off right to the max line. A couple days later I got the wrench light and the code read P0217 engine coolant over temperature condition. I cleared the code the next day but the wrench is still there with no code popping up.

Now even in 65 degree weather in the morning the coolant easily gets to 200+ degrees with the AC off. In the afternoons it gets to 230 degrees without getting in boost very much with 80-96 degree weather.

I want to replace the rad with mountune or mishimoto, but need to wait till winter to save the money for it. Any other suggestions in the meantime?


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M-Sport fan

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Princeton, N.J.
#4
I'm running a ~70/30 mix (in the SUMMER!), along with a quart of the Kool-It (Lubegard) additive, even though many claim it does nothing at all, in the factory radiator.

My Ultra Gauge only ever shows temps, even in 95*F+ ambient temps, over 195*F when the car is sitting still and idling, or in slow stop and go traffic.

Mine will actually drop temp, relatively quickly, when I turn on the air while idling sitting still, or in slow stop and go traffic, at least for a while, due to the high speed fan kicking on.

IF I could have a manual over-ride, high speed fan switch somehow wired into the fan circuit, the coolant temps would never go above 190*F, even with the factory radiator, regardless of the outside ambient temps, at least for non-hooning/non open tracking driving. [wink]

VENDORS/entrepreneurs on here; are you listening, is this even possible at all with our ECUs/etc.?? [dunno]
 


Last edited:
OP
Blk16 FiST
Messages
153
Likes
102
Location
Woodbridge, VA, USA
Thread Starter #6
Are you running 50/50 mix? Reduce the mixture. Run a 70/30 at most.
Stupid question, I’ve read it somewhere before but how do you get the 70/30 mix? And what kind of water do you put in it again?


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OP
Blk16 FiST
Messages
153
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102
Location
Woodbridge, VA, USA
Thread Starter #8
Distilled water. Buy a big empty jug and some measuring cups.
[emoji106] and is it 70 coolant/ 30 water? I know super noob question.. and how many gallons does our coolant system take?


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Jabbit

2000 Post Club
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Location
New England
#9
[emoji106] and is it 70 coolant/ 30 water? I know super noob question.. and how many gallons does our coolant system take?


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Opposite. 70 water 30 coolant. Nothing cools better than distilled water. Not sure about stock, I've only run with an upgraded radiator. Should be in your manual. No such thing as a noob question. Nobody is born with knowledge, we all learn different ways.
 


Dash

Member
Messages
33
Likes
25
Location
CA
#10
How do you check to see if it’s sticky/ closed? Never really messed with cooling stuff..


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When your car temp is in operating temperature or whatever your thermostat temp is, check the coolant hose connected to the thermostat housing. If that hose is still cold and not getting to the same temperature as the coolant hose on top of your radiator then you know its stuck closed. If the temperature varies by more than ~20 degrees then it's probably sticky and not opening all the way.

Best way is to remove it and test it but these are not the easiest to take out.
 


TemecFist

Active member
Messages
777
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615
Location
Temecula
#12
I'm running a ~70/30 mix (in the SUMMER!), along with a quart of the Kool-It (Lubegard) additive, even though many claim it does nothing at all, in the factory radiator.

My Ultra Gauge only ever shows temps, even in 95*F+ ambient temps, over 195*F when the car is sitting still and idling, or in slow stop and go traffic.

Mine will actually drop temp, relatively quickly, when I turn on the air while idling sitting still, or in slow stop and go traffic, at least for a while, due to the high speed fan kicking on.

IF I could have a manual over-ride, high speed fan switch somehow wired into the fan circuit, the coolant temps would never go above 190*F, even with the factory radiator, regardless of the outside ambient temps, at least for non-hooning/non open tracking driving. [wink]

VENDORS/entrepreneurs on here; are you listening, is this even possible at all with our ECUs/etc.?? [dunno]
Tap a switch into the fan wires. Easy peasy
 


TemecFist

Active member
Messages
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615
Location
Temecula
#14
Tuners also have access to this already. It’s not a great fix for the problem imo. I have so much peace of mind after installing the mountune.
Agreed. The Mountune radiator was the first mod I replaced (that and the intercooler). I've never had any problems with cooling......knock on wood.
 


SteveS

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Osage Beach, MO, USA
#15
If you buy 50/50 coolant and want to make 70/30, you'll have to do a little math to arrive at the correct amount of water to add. And you can't trust 70/30 for use in subfreezing temperatures.
 


Dash

Member
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Location
CA
#16
A lot of people here talking about your coolant ratio. I honestly don't think it'll make that big of a difference if any at all. His Temps are going up to 230 during normal driving...
 


OP
Blk16 FiST
Messages
153
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Location
Woodbridge, VA, USA
Thread Starter #17
A lot of people here talking about your coolant ratio. I honestly don't think it'll make that big of a difference if any at all. His Temps are going up to 230 during normal driving...
The thing is, once I coast down a hill at around 45mph or more it will cool down 10-15 degrees.. but 25-35mph in 3rd will maintain at 215 degrees once it’s up there.

It will also hit 160 degrees driving a mile down a 25mph road within 5 mins of starting the car


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TemecFist

Active member
Messages
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615
Location
Temecula
#18
If you buy 50/50 coolant and want to make 70/30, you'll have to do a little math to arrive at the correct amount of water to add. And you can't trust 70/30 for use in subfreezing temperatures.
A 70/30 mix (70% water 30% antifreeze) will protect down to 5*. If it's colder than 5*, and your still overheating.....you have serious issues somewhere else.


Edit. Had to fix this post.
 


Last edited:

Dpro

6000 Post Club
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Location
Los Feliz (In the City of Angels) aka Los Angeles
#19
The thing is, once I coast down a hill at around 45mph or more it will cool down 10-15 degrees.. but 25-35mph in 3rd will maintain at 215 degrees once it’s up there.

It will also hit 160 degrees driving a mile down a 25mph road within 5 mins of starting the car


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160 degrees driving down the road your thermostat is not even open unless you have a 160 degree thermostat you are basically running off your heater core at that point. Unless you have your heater set to full cold.
 


TemecFist

Active member
Messages
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615
Location
Temecula
#20
A lot of people here talking about your coolant ratio. I honestly don't think it'll make that big of a difference if any at all. His Temps are going up to 230 during normal driving...
Sorry my friend, but you're wrong. I run a 10/90 mix in my track car, and it definitely helps. I've never had my coolant temps go above 220*.....ever.
Even the GTR comes with a mix of 70/30, unless you have the cold weather package, then the mix is 50/50.
 




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