I've been seeing some conflicting info about the cooling fan in the c4, what temp is the oem fan supposed to kick on?

 

Factory specs are around 220 degrees.[8D]

 

Mine kicks on at 200 but this car is a mystery sometimes and some reprogramming was probably done before I acquired it.

 

Clayton, fans are controlled by relay based on temp readings and a/c reqests, sometimes what the ECM is seeing doesn't correspond to Temp senders.

 

The sensor that turns on the fan is seperate than the coolant temp sensor. My kicks on right at 227. 225 before i replaced the coolant temp sensor.

 

ok which temp reading does the ecm look at to turn on the fans? i noticed that there is a phsical guage and a digital guage in the speedo information. i also noticed they do not correspond to each other. the digital read is always lower. so which is it i trust when looking at temps and which one does the relay/ecm respond to?

 

Coolant Temp sensor with 2 wires, usually black/yellow wires.

 

well actually i was wanting to know if the physical hand type guage or the digital guage in the cluster is what to trust the most. lol. thanks.

 

Installed upgrade relay from ecklers, it kicks on at about 224

 

The coolant temperature sensor is located on the front of the engine and controls the digital readout in the car and also tells the computer when to engage the fan. The temperature sending unit is located in the head on the passenger side in-between the rear two sparkplugs. (at least on my 92 lt1) Seeing how i could care less what the temperature is getting at the water pump, I would rely on the temperature at the heads where getting too hot will cause you the real problems. The temperature at the water pump will, in my experience, always be colder than the temperature at the heads. As for the temperature the fans are supposed to kick on at, it is either 228 or 238, i can't remember.