Cooling Fan
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what year fans on mine come on at 228 and 238 I go by the digital not the analog might want to clean inbetween the radiator. and they all get hotter sitting.
Last edited by antfarmer2; Dec 11, 2015 at 01:20 PM.
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From: Lacey WA RVN 68-69
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What temperature do you see on the digital readout at idle and when driving the car?
What year is the car? Early C4's have a single fan behind the radiator (there may be a optional small fan in front of the A/C condensor. LAter C4's will have two fans behind the radiator. Also, C4's can have different temperature rated thermostats that will determine what the normal coolant temperature is.
There are sensors on the engine that send signals to the ECM to operate the cooling fans. As mentioned, there are high and low coolant temp values that the ECM uses to turn fans on and off.
When you turn the A/C on, the ECM turns the engine fan(s) on. With the engine at normal operating temp (lets say at around 195 degrees) is the main fan running? If not, turn the A/C on. Does the fan run?
What year is the car? Early C4's have a single fan behind the radiator (there may be a optional small fan in front of the A/C condensor. LAter C4's will have two fans behind the radiator. Also, C4's can have different temperature rated thermostats that will determine what the normal coolant temperature is.
There are sensors on the engine that send signals to the ECM to operate the cooling fans. As mentioned, there are high and low coolant temp values that the ECM uses to turn fans on and off.
When you turn the A/C on, the ECM turns the engine fan(s) on. With the engine at normal operating temp (lets say at around 195 degrees) is the main fan running? If not, turn the A/C on. Does the fan run?
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It is a 95 LT-1. The temp. normally runs about 180 with A/C on normal speed and at idle. Without AC a bit higher and at idle runs up past the 3/4 on gauge comes down some at driving speed.. Think temp is way to high in none A/C mode when at idle. Fear is engine damage but I am out of my league.
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It is a 95 LT-1. The temp. normally runs about 180 with A/C on normal speed and at idle. Without AC a bit higher and at idle runs up past the 3/4 on gauge comes down some at driving speed.. Think temp is way to high in none A/C mode when at idle. Fear is engine damage but I am out of my league.
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It is a 95 LT-1. The temp. normally runs about 180 with A/C on normal speed and at idle. Without AC a bit higher and at idle runs up past the 3/4 on gauge comes down some at driving speed.. Think temp is way to high in none A/C mode when at idle. Fear is engine damage but I am out of my league.
Even so, that analog gauge your looking at does not even have a linear scale. So, it is next to impossible to tell what the actual temp being displayed really is.
Unless the needle is actually into the "shaded" area at the upper end of the scale, your temp is not too hot.
Push the "Gauge" button and cycle through all of the options displayed.
One of them is engine coolant temp. Displayed next to the fuel gauge below the speedometer.
The temp displayed there will be more accurate, but it will still be hotter at idle than your probably used too.
Normal when moving at any speed above 25mph = 190°F - 200°F
Normal in stop n go traffic or at idle = 200°F - 235°F
The temp will rise and fall as the cooling fans kick on and off.
At highway speed the temp should remain constant.
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What temperature do you see on the digital readout at idle and when driving the car?
What year is the car? Early C4's have a single fan behind the radiator (there may be a optional small fan in front of the A/C condensor. LAter C4's will have two fans behind the radiator. Also, C4's can have different temperature rated thermostats that will determine what the normal coolant temperature is.
There are sensors on the engine that send signals to the ECM to operate the cooling fans. As mentioned, there are high and low coolant temp values that the ECM uses to turn fans on and off.
When you turn the A/C on, the ECM turns the engine fan(s) on. With the engine at normal operating temp (lets say at around 195 degrees) is the main fan running? If not, turn the A/C on. Does the fan run?
What year is the car? Early C4's have a single fan behind the radiator (there may be a optional small fan in front of the A/C condensor. LAter C4's will have two fans behind the radiator. Also, C4's can have different temperature rated thermostats that will determine what the normal coolant temperature is.
There are sensors on the engine that send signals to the ECM to operate the cooling fans. As mentioned, there are high and low coolant temp values that the ECM uses to turn fans on and off.
When you turn the A/C on, the ECM turns the engine fan(s) on. With the engine at normal operating temp (lets say at around 195 degrees) is the main fan running? If not, turn the A/C on. Does the fan run?
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From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
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I agree - but last week while stuck in delayed traffic analog gauge ran up past 3/4 mark (250). That bothered me (did not check digital temp. Should fans come on with A/C off to cool temp?
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From: Rolla Missouri
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St. Jude Donor '10 thru '25
So, there is no way you could tell if the temp reading was 200 or 250.
3/4 on the display is pretty normal.
And yes, the fans will come on with the A/C off.
But they won't come on until the temp reaches the "fan-on" program settings for your year car.
Not sure for the '95, but it will be approx. 228°F (when looking at the digital display)
At that temp, your analog gauge needle will be very close to the upper end toward that shaded area.
But the needle should not actually make it into the shaded area.
That analog gauge is just about useless really, as all it does is scare the crap out of people.
If your temps really do get too hot, you will also get a "check gauges" light display.
With the proper coolant mix and pressure, your coolant does not boil until approx. 265°F
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From: Lacey WA RVN 68-69
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One thing you really should do is to leave the digital display showing the coolant temp. As mentioned, the analog temp gauge is not linear and the chance are it won't even be as accurate as the digital readout.
While the digital display does provide good data, the coolant temp is probable the most important display especially if you think you may have some sort of problem. But from the temp values you posted, your cooling system is fine.
While the digital display does provide good data, the coolant temp is probable the most important display especially if you think you may have some sort of problem. But from the temp values you posted, your cooling system is fine.