Guys I am stumped...
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apeiron
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Guys I am stumped...
My car will maintain a steady 85c with the air conditioning on at idle. If I turn the air conditioning off, the water temp will climb till 99c and then the fans kick in and begin the cool the temps down.
Why in the hell is my car running COOLER with a/c on than off? Any insight is appreciated, because I have no clue.
I have a fluidyne rad in place of the OEM
Why in the hell is my car running COOLER with a/c on than off? Any insight is appreciated, because I have no clue.
I have a fluidyne rad in place of the OEM
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apeiron
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Im not seeing a 3 degree variance though... with the a/c on it will maintain 85-90 all day.
With out a/c, and before I had the PFC, it would shoot all the way to 108 before the fans would kick in.
Could it possibly be my thermostat is bad? On my water temp gauge (I have mounted on the 83mm tubing coming from the filler neck TO the radiator) it will read 94 but the PFC water temp reading shows 84-88.
My only guess is that the car's afrs gets thrown off when the a/c is off and likely running rich...
Like I said -- I am stumped
Also one other question for anyone that may have experience with this -- when I turn my car on from a cold start the PFC will read approx 14.4 volts, once the car is fully warmed it reads 13.8 volts..
With out a/c, and before I had the PFC, it would shoot all the way to 108 before the fans would kick in.
Could it possibly be my thermostat is bad? On my water temp gauge (I have mounted on the 83mm tubing coming from the filler neck TO the radiator) it will read 94 but the PFC water temp reading shows 84-88.
My only guess is that the car's afrs gets thrown off when the a/c is off and likely running rich...
Like I said -- I am stumped
Also one other question for anyone that may have experience with this -- when I turn my car on from a cold start the PFC will read approx 14.4 volts, once the car is fully warmed it reads 13.8 volts..
#10
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#11
my car is having the exact problem as yours. I always have to drive with the AC on in the #1 fan speed because it runs cooler with the AC on. I was having overheating problems until I noticed my fans don't kick in till the car is very HOT! So the AC manually turns on the fans at any given time. After I started doing that my car wasn't overheating anymore, if you know how to fix this let me know!! koyo rad + flex-a-lite fans are on the way so hopefully that will fix the problem or maybe my thermostat is peaced....
#12
Another trick is to turn on the parking lights. This will cause the ECU to turn the fans on at a lower temperature than it usually would. You can also change the thermoswitch to an FC thermoswitch. Lowers the temperature at which the ECU activates the fans. I can't tell you what the different temps are, but I think it turns on about 10 to 15 degrees sooner than the FD thermoswitch.
#14
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you could always use a datalogit and check what coolant temp the pfc has the fans set to come on for. When i needed my car to pass emissions, we set the coolant temp higher in the pfc so it would run hotter, and then adjusted it back down after. It could be that the fan parameter is set too high, and you can fix the problem by adjusting the fan temp threshold lower.
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Another trick is to turn on the parking lights. This will cause the ECU to turn the fans on at a lower temperature than it usually would. You can also change the thermoswitch to an FC thermoswitch. Lowers the temperature at which the ECU activates the fans. I can't tell you what the different temps are, but I think it turns on about 10 to 15 degrees sooner than the FD thermoswitch.
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FC thermoswitch 95 deg. C
FD thermoswitch 108 deg. C
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/its-official-do-not-buy-miata-thermoswitch-until-you-read-397156/
FD thermoswitch 108 deg. C
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/its-official-do-not-buy-miata-thermoswitch-until-you-read-397156/
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