C4 Corvette...1991 normal temperature question.

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'just have a question about my 1991 corvette. What is the normal operating temperature of this models?

I had the Thermostat and water pump recently replaced when my pump started making noise and now it's showing half to more than half of the gauge especially on the highway. Is this normal?
Is my vette starting to overheat after the water pump replacement?

Anyone has an input on this? Thanks in advance !

 

I remember my old 88 L98 was usually around 208.

 

after replacing water pump and thermostat, my 92 LT1 runs around 208/212... I am ok with that here in the South Texas heat...

 

Look in the C-4 General for my response......................

 

Hold down both the up and down arrows on the heater fan control for 10-15 seconds. The heater fan control display should go to 00 after you've held both buttons down long enough. Once it says 00, use the up arrow to cycle to number 16, then press the button with the picture of the fan on it. That should show you what the ECM is seeing for coolant temperature, in degrees C. The computer uses a different sensor than the dash mounted gauge, and the dash mounted gauge (at least the one in my 91) isn't very accurate.

My 91 usually runs about 85-90 degrees C, maybe 95 with the AC on. If I just sit in traffic on a 100 degree day, with the AC on, it will heat up forever, the cooling system can't keep up.

Rolling down the freeway, AC on or off, I am usually about 85, sometimes as low as 78-79 if it's a cool night.

I am using a 160 degree thermostat, but it doesn't help keep the car cooler. It takes the car longer to reach 85 degrees C, but opening the thermostat at ~160 F VS ~190 F doesn't make a difference on sustainted temperatures, all it does is delay warm up. If you use car as a daily driver, the stock thermostat is probably the way to go. Delaying warm up can be a little harder on parts, the only reason I do it is so that I can cool the car more easily between rounds at the drag strip.

Good luck, let us know what you find.

 

I have the same year. My gauge is just under 1/2 at cruising speeds. Yours sounds a little hot. When I sit in traffic I will heat up almost to the overheat mark before the second fan kicks on.

Check your radiator for debris. Look through the opening on the pass side. You can hose it off if there's dirt. It could be this.

 

You will be suprised if you have never cleaned inside the radiator shroud. I think I found a dead bird when I took mine apart.

The mess of leaves and debris easily covered 25-30% of the radiator.

Also, is your front air dam in place? My 91 came without the center part. I found out that when cruising in traffic at 25+ MPH it really helps get air up into the radiator. Before replacing it I had to do at least 45 to get enough air flow to affect temp readings. Unfortunately it doesn't help sitting in traffic.

Another idea is have you really done a thorough flush of the system?? I don't mean just empty the radiator, fill it up then flush it out. But also remove the knock sensor from one side of the block and the drain plug from the other side and really see what's in there. I'm currently replacing the heads on my 91 because I think something blocked on my driver's side. When flushing the block the drain holes got stopped up multiple times by big hunks of gunk. Your water pump may be new and up to the task but if the arteries are clogged, not a lot is going to circulate.