I am at wits end on why my fans are not coming on. I have changed the Engine Coolant Temp Sensor and checked the relays but still have no fans. I hot wired the fans and they do operate. If I turn on the AC the fans do come on but they don't sound like they are at full speed. I can disconnect the engine temp sensor and the fans kick into high gear but they will not come on automaticly.

What am I missing?

 

Stock fans don't come on until 226°. What temps are you reaching that the fans are not coming on?

Your description of when they do come on sounds normal. What year car and how many fan relays do you have?

 

Doh, stupid me forgot the important stuff.

This is a 97 Z28, 3 relay system. I shut down the car before gauge hits red, I am guessing the fans should be on long before that. This is all just sitting at idle.

I changed the thermostat, 195, last night and bled the system until I got coolent out of the bleed fittings. Drove it around the block a couple of times, ran hotter than normal but under 210 according to the gauge. Sat in the garage at idle for 5 min max and temp was well on its way to red and still no fan. I have never recalled seeing the temp gauge over 210, even after sitting for 20 min with the ac on.