Help! 1995 LT1 overheats

[Nucman]

Hello everyone, I own a 95 coupe with the 350ci. I noticed the analog gauge would say the temp was at 260 degrees but the digital read out says the engine is cool and is at 212 degrees. When the gauge first said it was at 260 degrees I could not pull over right away so I drove it a few hundred more yards and the temp dropped down to 235. So I am not sure if the car is overheating or not, I have replaced the thermostat , the radiator, and put in another fan switch to turn on the fans at 200 degrees. There are no leaks, no water in the oil, and both fans work. The highest I have ever seen the digital gauge go is about 240 degrees thats with a outside temp of 100 degrees and the AC on. The car never boils over but it does fill the overflow tank at times. I can drive the car for a couple hours and the temp stays at about 210-215 degrees, if I stop and turn off the car for 30 minutes or so and go driving again the next thing I know the analog gauge pegs out at 260 degrees and the digital says 235 up to 240 degrees but never says the engine is hot. Any help would be great, this is driving me nuts !!!

 

[norwegianvette]

Hello everyone, I own a 95 coupe with the 350ci. I noticed the analog gauge would say the temp was at 260 degrees but the digital read out says the engine is cool and is at 212 degrees. When the gauge first said it was at 260 degrees I could not pull over right away so I drove it a few hundred more yards and the temp dropped down to 235. So I am not sure if the car is overheating or not, I have replaced the thermostat , the radiator, and put in another fan switch to turn on the fans at 200 degrees. There are no leaks, no water in the oil, and both fans work. The highest I have ever seen the digital gauge go is about 240 degrees thats with a outside temp of 100 degrees and the AC on. The car never boils over but it does fill the overflow tank at times. I can drive the car for a couple hours and the temp stays at about 210-215 degrees, if I stop and turn off the car for 30 minutes or so and go driving again the next thing I know the analog gauge pegs out at 260 degrees and the digital says 235 up to 240 degrees but never says the engine is hot. Any help would be great, this is driving me nuts !!!

Tried to replace the sender, might be defect. Also clean out the radiator, gets full of flies and other debris over the years and this will restrict the volume of air coming through and then again less cooling.

 

[Rabbit]

Check the radiator cap?

 

[Rex S]

When you had the cooling system open and then refilled the coolant did you open the air purge? May have air trapped in the system.

 

[Nucman]

Getting better

Yes replaced the radiator cap, and purged the system of air. Just found that the water line that runs from the water resiviour to the top of the radiator and intake maifold was partly blocked. Blew it out with air and the car seems to run much cooler. But same thing: if i let it sit a while and go out to drive again the temp gauge will go to 260 degrees, but as soon as I start driving it gos to normal and seems to stay there now.