While cruising down the road at anything under 2K to 3K RPM my coolant temp goes up about 10 to 15 degrees. If I downshift and run it up through the gears the temperature drops back down to 195 or so, even with a 180 stat. I'm sure the autocrap thermostat is junk, and I will replace it, but why the temperature creep? The car did this even with the old factory thermostat. Is my w/p shot, or has anyone else experienced this?

All posts are welcome. I'm still new to this reverse cooling stuff, so please bear with me. BTW- I am using an Auto-Meter water temp gauge and a Tech 2 to verify coolant temps, so I know they're right. Thanks in advance!

 

That almost sounds normal?

Bleed your system a few times, change your stat, and see if those help at all.

 

Is your air dam intact? Without it, coolant temps will climb while cruising.

 

i was thinking a clogged radiator...

the pump isn't circulating enough water to keep it cool when at low rpm...but once the pump really "pumps" at higher rpms maybe it's enough force to get water through the radiator.

do the obvious, thermostat, flush and a good bleed

 

It you bought a thermostat at Autozone, you probably got the wrong one, because it's in their database as a small block Chevy t-stat, and they are not the same.

 

My cobalt guage reads 195-200 while crusing. Isnt this normal, I think so.

 

Yeah, the radiator may be plugged. The air dam IS intact, and the thermostat IS the correct one. I will be flushing the entire cooling system in april when the engine comes out for a freshening. BTW, did the 95's come with Dexcool? I'm pretty sure that if mine did, someone went ahead and filled it with green, and now it's turned to sludge. Oh well, all will be better after the engine is back together and running.

Thanks for the posts, and keep them coming.

 

If it came with Dexcool, it would have a sticker under the hood saying so.

Creeping temps are usually the result of lack of flow (could be air or coolant). Another possibility is that there is too high of a concentration of coolant to water. Coolant does not dissipate heat as well as water does. 50/50 usually works the best for protection and cooling.