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Discussion Starter #1
After the engine gets to around 160 both fans start and won't quit unless I shut the engine off. New radiator, new coolant sensor and thermostat, new a/c radiator, compressor, drier etc. Where do I go from now? Get me going in the right direction. Thanks.
 

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Discussion Starter #3
It's the regular one. If I'm not mistaken 195*......
 

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It's the regular one. If I'm not mistaken 195*......
There are two temperature sensors... The one in the head (Passenger side lower on the head towards the middle if I recall properly) only feeds your Gauge. The one in the water pump feeds the PCM. Both running fans is a fail safe mode when the sensor is not connected or not working properly. Check the plug and wiring to the sensor in your water pump and insure it is correct. if not an issue then you likely have an issue with the sensor.

(I BELIEVE it is in the water pump. Or near it. Been over a decade since I last looked at my car under the hood.)
 

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Get that 195 stat out of there pronto. 180 degree max,but many if not most of us prefer the 160... Usually has to be specially ordered...
 

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Discussion Starter #6
Stat is actually 180. The coolant sensor is new. It's probably the feed. I'll check out tonight. I'll let you know how it turns out. Thanks!!!!
 

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Just a suggestion, make sure your evap solenoid plug is plugged in. ACTUALLY.. make sure all plugs are plugged in. I know that the few times I have left plugs undone, sometimes it kicked on both fans.

These are goofy ass cars.
 

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We've checked all grounds and they're good. We're getting 5 volts at the sensor as the diagnostic book says we should. Unless the new sensor is junk we're heading for the PCM. We'll also check all connector including evap solenoid. Keep the info coming. Thanks for all the input!
 

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The fan-on temp thresholds may have been reprogrammed too low for the installed thermostat.

With a 195°F thermostat installed, the fans will be on constantly, sans Check Engine light, if the fan-on thresholds are UNDER 99°C / 210°F.
With a 180°F thermostat installed, the fans will be on constantly, sans Check Engine light, if the fan-on thresholds are UNDER 90°C / 194°F.
With a 160°F thermostat installed, the fans will be on constantly, sans Check Engine light, if the fan-on thresholds are UNDER 80°C / 176°F.

If there is no Check Engine light, & the fan-on thresholds are appropriate but still blowing constantly, only other thing I can think of is if the pcm is somehow erroneously receiving an excessively high AC psi reading.

If the Check Engine light is on while both fans are blowing, check the CTS sensor wiring.
 
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