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Discussion Starter · #1 ·
Hello guys, since day one my ST has been having problems with temps, both coolant and oil. Whenever I turn on my A/C the coolant temp will never past the 1/4 needle gauge, if the ac is off it will get to the ideal temperature (half way). If I'm at ideal temperature and turn on the AC the temp will fall again to the first mark. Oil temp is always at 1st mark unless I punish the car ( trackdays or something). The dealer already checked the thermostat and it is working correctly, an update corrected the idle stalling problem. Do any of you have any idea about what could it be ?
 

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I know the oil temp usually takes awhile to warm up for just about everyone.

As for the coolant temp, it really just sounds like the thermostat is opening too early. I know you said you already took it to the dealer, but did they replace the thermostat? Also might want to look at the coolant temp sensor. Maybe its just faulty.
 

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Probably an electrical issue; once warmed up there is no reason for the temps to drop.
 

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Discussion Starter · #5 ·
A/C or heat? A/C should put more load on the engine and heat it up more. Sounds like a sensor issue to me.
A/C , heat works normally but I never use it.

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Discussion Starter · #6 ·
I know the oil temp usually takes awhile to warm up for just about everyone.

As for the coolant temp, it really just sounds like the thermostat is opening too early. I know you said you already took it to the dealer, but did they replace the thermostat? Also might want to look at the coolant temp sensor. Maybe its just faulty.
The thermostat ia not opening early because it works fine if the a/c is off. The dealer also took engine temps with their laser thermometers and it is indeed colder than it is supposed to be.

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Discussion Starter · #7 ·
Probably an electrical issue; once warmed up there is no reason for the temps to drop.
Any idea where to look? Could it be related to the harness recall fix ?

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Any idea where to look? Could it be related to the harness recall fix ?

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No idea; electronics and I do not get along well, but, I would think either a sensor or the Electronic Control Unit (ECU).
 
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