Just replaced my water pump and put it in a new 180 thermostat....... started car up, after 10 minutes car is hot, nearing 220.... gets a little past 220 and I've noticed that the fan has STILL not come on. First thing I should do is replace fan relays right?????

(fan and fan motor are no more than 2 years old, as is radiator)

 

well try and wait alittle longer to see if the driver side comes on.

since ur still running the stock chip and fanswitch the fans will still work on the stock turn on temps.

if u dont like seeing that high of a temp then maybe just add in toggle switches to ground the relays when u want to turns the fans on.

 

What is the stock turn-on temp BTW?

 

Stock temp dual fan setup is 225 for primary, 234 for aux. MD is right, the only way you will see lower temp is when you are moving with a lower stat. Dual factory fan setup, the ECM controls the primary and aux is controlled by a switch in the passenger side of the block. Best way is to edit the prom to lower primary turn on temp, if you put in a lower temp fan switch like many guys do if the aux comes on before the primary BOTH fans will run as the ECM will default when it sees the aux on first. The factory or stock setup is the best way to leave it.

 

This is a pain in the azz, but I had to do it because I only had one fan, and the ECM didn't control it. Rewire both fans thru 2 different thermal fan switches, and you can control when they come on by the values on the sensors. It sucked, but now everything is automatic, and it works just great