I know there are numerous threads regarding this. I have a 96. Bone stock Automatic. Have owned it for years. Has 86K on it. Runs great with no issues other than it runs REALLY hot. Here is an example. Yesterday I went for a 20 mile drive up the coast. Some stop and go but most of the time I am driving around 35mph average. Temp outside is 63 degrees. .I have the numerical temp gauge on and the standard gauge both on. My car was running at 226 degrees after about 15 minutes of driving.. I put the AC on and it went down to 205 and at one point it was at 198. Shut the AC off and it jumps back up to the 220's. Traditional temp gauge needle wasn't pegged but it was past the 3rd hash mark. My wife was freaking out because she was convinced we were going to overheat. I know there are numerous threads stating don't worry about it and that all LT1's run this hot and its the design of the cooling system etc... but after years of wondering when this car is eventually going to over heat I figured I would ask the question. There is no debris blocking the radiator.
I am now contemplating replacing the stock single core radiator with a 2 or 3 core and be done with it. Its unnerving driving around with an almost pegged temp gauge.. especially when its only 63 degrees out and I am cruising at 35mph.

 

If the temp went down when you turned the A/C on it tells me that was because the fan came on. Try just idling (with A/C off) and watch temp gauge to see if the fan comes on at around 229. If not then fan is the problem. My 95 started running hot a few weeks ago and found the fans didn't turn on at temp and when A/C was on. Turned out the fuse was blown.

In your case it could be one of the fan relays or sensors are bad,

 

Aren't those cars designed to run at those temperatures?

 

That is the general response but I ask you.... knowing all the engineering put into the C4.. especially the last year 1996.... you would think the engineers would at least put in a temp gauge that wouldn't be almost pegged to scare the crap out of the owners of these cars.
If ANY other car showed an almost pegged temp gauge and a 227 reading on the digital temp display you would be pulling it into the repair shop.
It doesn't make sense and I refuse to believe its normal. I think they put an undersized radiator in these cars and even though they don't generally overheat its still undercooled. These cars should be running at around 195 in any condition. Especially 63 degrees out doing 35mph along the coast.

 

220's is nothing, but still hotter that should be. When is the last time you had the radiator out for good cleaning? You can't see the crap that gets in the fins from above. Likely all it needs

 

That sounds completely normal to me, my 96 does the exact same thing... Scared the hell out of me at first, then i went on here and read the forums and ill be darned, if thats just normal operation.

 

I have a 96 automatic that is stock. I run on the interstate when it is 95 degrees at 186 degrees. I have installed a Dewitts single row radiator, flushed with my shop vac flushing system, cleaned the condenser of small rocks from the backside with high pressure air and installed a fail safe thermostat which opens faster than the AC Delco. Your temps (while technically fine) would scare the crap out of me. Dan

 

Shop vac flush works! - CorvetteForum - Chevrolet Corvette Forum Discussion

The factory put in stop leak. It forms a brown scum. The block needs to be vigorously scoured of this brown scum. Just draining the block out of the knocks just gets the scum in suspension. There is 100 times that amount stuck to the inside of the block impeding heat transfer. It is a problem that requires an "all of the above" solution. Dan edit: does anyone think that way back in 1996 that Chevy sold a Corvette that got up to 230 degrees on the drive home after shelling out 35k and told the new owner that it was just normal?

 

Exactly... I say no they didn't because if they did they would be getting just about every owner returning the car back to the dealership for servicing. A good proper flush will be my first step and I need to check the relay's that turn the fans on. They come on with the AC on but I am not sure they are turning on with it off.

 

Dan edit: does anyone think that way back in 1996 that Chevy sold a Corvette that got up to 230 degrees on the drive home after shelling out 35k and told the new owner that it was just normal?

Haha, I reckon the seller would say something like this: Well, the engineers at GM or Chevrolet or Corvette all saw fit to put a tempreature swith to turn on the cooling fan at 229degrees... So yeah, thats normal, take it up with the engeneering department lol.

 

Very easy to check by just start and sit at idle with A/C off and see if it comes on as it gets to 228/229. It does get owners worried when they see the analog gauge gets closer to closer to "pegged" area. Long as the fans are operating correctly you'd see the temps lowering very quickly.

 

Previous owner bubba’d my fan relays to turn on with the ignition. Car runs 185 most of the time, idling in traffic it’ll creep to 200-205.
I don’t have any complaints with it so I have not undone it

 

I am like the same as I live in Iowa and only drive in the summer so I usually have the AC on. It works the same. Dan

 

make sure no leaks, including cap. then if not cool enough flush and look into Dewitts replament. my 1992 runs 186 to 196

 

I forgot to mention one of my fans was making some funny noises a couple of years ago and I replaced both of the fan motors. In my opinion, the airflow was 30% more than the quarter century old fan motors. Dan

 

There is not enough airflow through the radiator on these cars to cool at 35 mph. You need to go at least 50 in my experience. If you don’t do something to turn the fans on sooner a bigger radiator will just delay the problem. Mine runs 185 on the highway. I usually turn on the ac if I’m in traffic and that keeps the temps in low 200’s.

 

A 1996 has (2) fans and (3) Relays. Low speed (On at 226F) runs both fans at half-speed, High speed (On at 235F) runs both fans at full-speed. A/C turns both fans on at High speed.

For 1994-1996: First diagnostic: With cold engine, start and let idle with A/C on. (Fans should turn on from A/C head pressure long before engine temp reaches turn-on threshold.) Are both fans running with A/C ON? They should be. If = NO, only one fan in High speedcan be caused by a bad Low speed relay which is the only relay of the three with a single dk green wire.

To validate the cooling fans system and control. (Stock ECM calibration, not a "reflash"):
Coolant temperature <200F. A/C mode OFF. Start engine and let idle.
Watch digital coolant readout: At 226F both fans should come ON and run in Low speed.
> When they do, unplug the single relay with the dk green wire. Both fans should stop.
Watch digital coolant readout: At 236F, One fan should turn on in High speed.
> Reconnect the unplugged relay. Both fans should run in High speed.
Watch digital coolant readout: At 229F, both fans should revert to Low speed.
Watch digital coolant readout: At 219F both fans should turn OFF.

If the above tests pass, there may be radiator restriction or airflow blockage.
The "blockage" that makes a difference accumulates between the condenser and the radiator. Removing the upper shroud and taking a look is definitive. Taking a peek under the bumper isn't. You may be able to see something with a camera-scope between the condenser and the radiator, but I've never tried it.

 

My normal temperature sits around

 

I never even look at that gauge. I treat it as an on-off gauge. Dan

 

I do. About every 20 seconds. It is part of my "scan". I don't care or even attempt to deduce the "value" from the analog gauge, I'm only looking for the position of the needle to be what I expect it to be. If I want to know what the actual value is, I take off my polarized sun glasses so I can see the LCD, put on my readers, put the digital on "gauges" because it is normally on TRIP, and look at the temp. Obviously, just looking at the position of the needle is a lot quicker to tell me what I need to know: That coolant temperature is within normal range, and that it is still what it was 20 seconds earlier.

You don't need to know the actual temperature every time it is monitored, just that it is within the normal expected range. The position of the needle tells you that. Cheers.