Hello, now this is gonna sound weird but im telling you whats happening. My 93 Z gets real hot on the highway at speeds of 60 MPH or faster if im going at that speed for a constant amount of time. Yet when i idle or when i go at slower speeds for a constant period of time my temperature drops back down to where it should be running. Now this mostly gets the werst with the A/C on, but it still gets hot. On a short trip on the highway today down here in south florida, it was probly 84 deg outside and my temp gauge on my car after a few miles down the highway with the A/C on was getting dangerously close to the red area. I just put a new 180 deg thermostat in, all new coolant. I have no idea why i get so hot. Please give some advice.

Cory

 

Is the plastic dam still on the bottom of your car?

 

make sure the system is properly bled. These cooling systems are VERY finicky.

Check to make sure both fans are comming on. If not check the relays.

 

ya, bleed your coolent system. you might want to check your thermostat.

 

i bled the system with all new fluids and i put a new 180 deg thermostat in, no leaks, everythings there and all of its new. There are 3 things i believe i have limited it to. I may need a new radiator, considering its only at high speeds for a constant period of time, once i slow down for a while the temp goes right back down to operating temp. This could mean i got a semi-clogged radiator maybe. Or the water pump or air damn may be screwed up im not sure, couldnt see how if either one of those were wrong my car wouldnt run as good as it does, not to mention around town and at idle its perfect, right at operating temp and runs great and all is well. Im thinking the radiator, anyone think it could be something else?

Cory

 

Did you put in the correct long style thermostat specific to the LT1 reverse flow system?

Sounds like a flow problem - either coolant flow or air flow. Check the front of the radiator for plastic bags or other debris. Make sure you look all the way up to the top.

 

im gonna check the radiator for debris or anything else today. Im pretty sure i got the right thermostat but i may not have. I still have the box ill check shortly. Thanks

Cory