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A/C causing overheating

Messages
102
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51
Location
Indio, CA, USA
#1
So my car runs pretty damn good, the A/C blows cold and it has 59,000 miles. My issue is that where i live in California, its gets 120 degrees in the summer. My car will run at around 205-210°F and run normally, but once i turn the a/c on it will rise all the way up to 227°F and if i dont turn the compressor/A/C button off it will just keep climbing, its so annoying. My tune actually seems to help the situation out due to the fan speed being ramped up, but still not enough. Anyone have any ideas on how to fix this besides getting an expensive ass aftermarket radiator installed.
 


Messages
187
Likes
208
Location
Central CT
#2
Turn the tune off and remove the aftermarket intercooler or buy yourself a new radiator. It sucks, but those two things cause the stock radiator to underperform in high temps. I just went down this road.
Of course you could just run without AC for those days.
 


TyphoonFiST

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Rich-fizzield
#3
Are the Fans coming on when they A/C is on and your stopped and at operating Temp? I also second the Mountune or Mishimoto radiators. This will most likely solve the Overheating woes*

Sent from my SM-N975U1 using Tapatalk
 


dhminer

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Burlington, NC, USA
#4
Sad truth - none of the options are going to produce a good result and cost nothing. You can have a good result, or pay nothing. Only way to get good AC, low temps, most power is to upgrade radiator. FWIW, it's well worth the price if you can swing a few hundred bucks. Install is pretty easy. I had it done in ~6 hours and I'm slow af.

If upgrading radiator is out of the question (and you've verified the fan is working correctly), you could try running a higher % of water.
 


Mikey456

Active member
Messages
672
Likes
406
Location
Los Angeles
#5
Turn the tune off and remove the aftermarket intercooler or buy yourself a new radiator. It sucks, but those two things cause the stock radiator to underperform in high temps. I just went down this road.
Of course you could just run without AC for those days.
Turn the tune off and remove the aftermarket intercooler or buy yourself a new radiator. It sucks, but those two things cause the stock radiator to underperform in high temps. I just went down this road.
Of course you could just run without AC for those days.
Why would an aftermarket intercooler be a partial cause of overheating? Is it just the size that limits airflow to the radiator?
 


OP
Blanco_ST
Messages
102
Likes
51
Location
Indio, CA, USA
Thread Starter #7
Are the Fans coming on when they A/C is on and your stopped and at operating Temp? I also second the Mountune or Mishimoto radiators. This will most likely solve the Overheating woes*

Sent from my SM-N975U1 using Tapatalk
Yah the fan is basically on the whole time while driving up until i turn it off. all though i wish it would continue to spin even when the cars off just to keep cooling it down.
Damn I realize that im going to have to just purchase an aftermarket radiator.
 


OP
Blanco_ST
Messages
102
Likes
51
Location
Indio, CA, USA
Thread Starter #8
Sad truth - none of the options are going to produce a good result and cost nothing. You can have a good result, or pay nothing. Only way to get good AC, low temps, most power is to upgrade radiator. FWIW, it's well worth the price if you can swing a few hundred bucks. Install is pretty easy. I had it done in ~6 hours and I'm slow af.

If upgrading radiator is out of the question (and you've verified the fan is working correctly), you could try running a higher % of water.
Sad truth - none of the options are going to produce a good result and cost nothing. You can have a good result, or pay nothing. Only way to get good AC, low temps, most power is to upgrade radiator. FWIW, it's well worth the price if you can swing a few hundred bucks. Install is pretty easy. I had it done in ~6 hours and I'm slow af.

If upgrading radiator is out of the question (and you've verified the fan is working correctly), you could try running a higher % of water.
Thank you for this information 🤙🤙
 


OP
Blanco_ST
Messages
102
Likes
51
Location
Indio, CA, USA
Thread Starter #9
Sad truth - none of the options are going to produce a good result and cost nothing. You can have a good result, or pay nothing. Only way to get good AC, low temps, most power is to upgrade radiator. FWIW, it's well worth the price if you can swing a few hundred bucks. Install is pretty easy. I had it done in ~6 hours and I'm slow af.

If upgrading radiator is out of the question (and you've verified the fan is working correctly), you could try running a higher % of water.
FWIW im having some trouble finding that brand? Maybe im reading this wrong
 


Messages
41
Likes
32
Location
Albany
#11
I had the same experience the other day for the first time. I was idling in freeway traffic 10 minutes, maybe 93-94 degrees out. I just have stage 2 ots tune and the depo intercooler, no upgraded radiator yet.


Sent from my iPhone using Tapatalk
 


kivnul

1000 Post Club
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Location
Deer Park, WA
#12
Highly recommend Mountune radiator. I had some emails recently that made it look like they were having a sale, might be worth a look.
 


Messages
209
Likes
123
Location
Easton
#15
Some on here will claim that these have no/nada/ZERO effect at all on the coolant temps, even of the factory radiator, but I personally just don't see how they possibly could not. [wink]
If you think about it, it hurts in 2 ways.
1. It blocks a little more air flow to the radiator.
2. Being more efficient at heat transfer than stock IC, it has Hotter air coming through to the radiator!
(Still needs better radiator)

Sent from my Pixel 2 XL using Tapatalk
 


M-Sport fan

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Location
Princeton, N.J.
#16
If you think about it, it hurts in 2 ways.
1. It blocks a little more air flow to the radiator.
2. Being more efficient at heat transfer than stock IC, it has Hotter air coming through to the radiator!
(Still needs better radiator)

Sent from my Pixel 2 XL using Tapatalk
EXACTLY my thoughts as well, but others on here even with full radiator blockage size intercoolers vehemently deny this.
 


Intuit

3000 Post Club
Messages
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Location
South West Ohio
#17
Not sure how this system is setup. I could look it up in the manual if desired. But my prior car had a two speed fan. Like most modern cars it rarely ran the fan unless the A/C compressor was activated. That only defaulted to low speed. I never even knew it had another speed until a few years down the road it kicked into high or what I like to refer to as, "wind tunnel" mode. In some vehicles, that seldom-used high speed fan relay would fail. So they'd be stuck with having one fan speed. The two fan speeds could be tested via diagnostic mode.

So my question is, have you verified that the fan is capable of achieving all its turning speed?

EDIT: Some will inevitably assume that I'm saying it's not the radiator. Didn't say that. Just something else to check while you're adding that new radiator.
 


Dpro

6000 Post Club
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Location
Los Feliz (In the City of Angels)
#18
Not sure how this system is setup. I could look it up in the manual if desired. But my prior car had a two speed fan. Like most modern cars it rarely ran the fan unless the A/C compressor was activated. That only defaulted to low speed. I never even knew it had another speed until a few years down the road it kicked into high or what I like to refer to as, "wind tunnel" mode. In some vehicles, that seldom-used high speed fan relay would fail. So they'd be stuck with having one fan speed. The two fan speeds could be tested via diagnostic mode.

So my question is, have you verified that the fan is capable of achieving all its turning speed?

EDIT: Some will inevitably assume that I'm saying it's not the radiator. Didn't say that. Just something else to check while you're adding that new radiator.
While yes it could be that possibility though not likely on a newer car. OP is from Indio that is the Desert so I would hazard to say yes his fans are working fine and yes he needs to upgrade his radiator. I had the except thing happen to me here in Los Angeles. Oh and ya we were considered Desert once as well. :LOL: at people not considering LA a Desert.

Oh and that was with the stock intercooler on mine lol. I upgrade my intercooler and radiator at the same time. I have not had a problem with temps ever since even in 100 degree temps running the canyons on a bigger turbo a few weeks back I might add.
 


M-Sport fan

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Location
Princeton, N.J.
#19
^^^The CP-E is NOT one of the intercoolers which blocks the front surface of the whole radiator though.

But yes, I do not want to install my CP-E until I have a Mountune radiator to install at the very same time. [wink]
 


Intuit

3000 Post Club
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Location
South West Ohio
#20
@Dpro - I see my "EDIT:" message still didn't work. 😋

BTW, I did attempt to lookup the circuit diagram for the fan system earlier but the already ancient program from 2005 that Ford/Helm uses to show their diagrams has an apparent compatibility issue with Win10 21H1. 🙄
 


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