94 z28, auto. I recently replaced couple of my coolant hoses and now my engine is running on the hot side like 230 deg. I've bled the air from the two screws near the TB. It doesn't run hot all the time. It did it the day after the hose replacement and a couple of times last week. I always run the ac so the primary fan kicks on and I don't recall seeing it run higher than bout 180-190 before I did the repair.

What I've noticed is the secondary fan is not turning on. I checked the relays by swapping them around. The secondary fan comes on when powered up manually. I'm getting power to the "batt" and "ign" terminals of the relay. I haven't checked if the ecm is properly grounding the relay. My question is what temp should the secondary fan kick on?

I've soldered in a toggle s/w to the neg side of the relay to chassis ground if I need to turn it on. The vehicle does cool down when I activate the secondary fan. I'm planning to have my ecm programmed to turn on the fans alittle earlier. I'm hoping that it's just air pockets. Is there a specific way to bleed air out of the system?

 

bleed it again, and again, test the temp sensor on the water pump.

 

When the A/C is cycled on, your engine needs the secondary fan to keep cool, that's why it's there.
When running the A/C, your secondary fan isn't turning on and the engine is running hot.
When you hot-wire the second fan to turn on, the engine temp cools down.
So, why would you think the problem is anything but the secondary fan?

 

have you seen this, https://camaroforums.com/forum/93-02...ne-fans-54192/

 

Glad I found this, I thought mine was running hot and the fans not coming on, but I put a scanner on it while I was driving. Temps approach 230, one fan kicks on, temps drop back to @220, fan cuts off. My problem is the dash gauge is waaaayyy off. It indicates I'm running in the 240-250 range. I'm going to change the sensor in the block. Does a bunch of coolant escape when changing this sensor? If so, I assume the system must be bled again since it is being opened up?