Originally Posted by RRT vette

I spent about 45 minutes observing the coolant temperature operation range on my stock (never modified) 95 LT1 with 50,000 miles. I started the engine and let the temp rise. All of the info is while at idle and the outside temp 80*. Idle temp reached 228* before both fans came on and never saw the temp past 230* via digital guage. Analog guage was in the hash marks and showed approx. 250* from guessing, 260* being the highest number which is miss leading. The temp dropped to 217* and both fans cut off. With the A/C on the temps sat around 201-205* and never got lower or higher. This I consider normal at idle and when driving at about 55 mph the digital temp guage stays around 185-190* range.

I spent about 45 minutes observing the coolant temperature operation range on my stock (exhaust mods only) 86 L98 with 94,000 miles. Only modification to the coolant system is a 180* stat installed in Feb 06. I started the engine and let the temp rise. All the info is while at idle and the outside temp was 85*. Idle temp reached 227* before the fan came on and never saw the temp past 228* via only digital guage and verified by scan tool to be correct. The temp dropped to 220* and the fan cut off. With the A/C on the temp sat around 205-210* at idle and stayed there. I consider this normal at idle and when driving at about 55 mph the digital guage/scanner stays around 180*-185* range.

For those that have questioned the operation of the coolant system on early and late model C4's, refer to this as it is normal temperature ranges in all coditions. Temps may rise faster and drop slower in hotter weather, but the operation of the fans are the same, controled by the ECM.

Check between the A/C condenser for trash (bird nests, leaves, plastic bags, anything that will block air flow to the fins). Make sure the air is out of the coolant system as temps will stay on the hot side do to air pockets. Make sure the coolant level is full and there are no leaks in the system. Make sure the fan(s) are operating as they should. Use only the coolant the manual says (green for my 86 and other years and Dexcool for the 95-96).

Originally Posted by jda67gta

Don't trust the analog sweep gauges, use the digital read out. They are both driven by the ECM, but the digital is more accurate. 225 idling is on the money.

Originally Posted by joemojica

Got a '95 Corvette recently and I'm not too familiar with it yet. It does fine on the road but as I sit idling too long at a light, the temperature rises quickly. This can be nerve racking in rush hour traffic. I don't really want to make any unneeded repairs. Got any ideas? Appreciate any input.