Overheating GTP

Well, here we go again. I went out for a little ride after the s/c oil change. I started noticing I was running hot in traffic. It was getting to 190 and I had to keep my heat on full blast to maintain around 160. Temp. was 42 outside. I got home and just sat in my driveway with no heat on watching temp. Within 3 minutes running up close to 210. Help

Technically it is not overheating. What degree thermostat do you have installed? Around 190 is normal if you are stock. Even up to 210 could be normal especially in the winter during long idle periods because the cooling fans do not turn on until 220-230 degrees. During warmer months it may not be as noticeable because of the A/C. With A/C on or in Defrost with compressor running the cooling fans will turn on sooner than 220 degrees so the temperature gauge reading will look more reasonable.

I dont know what degree thermostat I am running. Whatever the car came with when I bought it. Should I take it out and look at it? Also I think I might be loosing coolant. I looked yesterday at my level and I put about a cup of water in it. When I look at it again it looks like it needs more coolant. I am going to flush the radiator today. Should I stick with the Dex-Cool? The top of the radiator cap has this sludgey build up as well as in the resevoir. The resevoir is empty but in the bottom of it its pretty gross looking. Also when I pooped the resevoit cap the hose that goes into the tank was not attached to the cap. I put it back on.

I am not going to freak out. I know this is a good car I just hope its not going to be one of those cars.

Should I crank it up and see if it will go over the 210? Looking at the temp guage I assume that every line is about 10 degrees.

Since you plan on flushing the cooling system it won't hurt to look at the thermostat. You never know what the previous owners did with the car or what parts were installed. The Dexcool sludge is common especially in the reservoir since it is not sealed and exposed to air. Air and Dexcool do not get along. When you drain the radiator inspect the coolant. Regardless since you may not know when the coolant was last changed out it is better to flush and replace the coolant. Based on my experiences Dexcool becomes worthless after about 5 years. I use Prestone Extended Life coolant which is OAT based like Dexcool and fully compatible with it. Remove the reservoir before you add the new coolant and thoroughly clean it out first.

To properly check coolant level check it at the radiator with engine cool and not at the reservoir. Check out the cooling system flush procedure below. Good luck.



I use Prestone Super Flush which is an additive you pour into the cooling system before doing the actual flush. For antifreeze/coolant I use Prestone Extended Life. It is in a yellow container and will appear green in color.

Here is a basic coolant flush procedure:

Install the flush T from the Prestone Flush Kit in the heater return line hose.

1. With engine cool, remove radiator cap and drain the radiator.
a. Turn drain plug (lower left engine-side of radiator) counter clockwise about 1/8 of a turn (may require a little force if it's not been opened in awhile--be careful because it's plastic). Use the end of a 1/4" drive handle. Plug will extend slightly as it loosens. Be sure to have a container in-place to collect the antifreeze.
2. Let all the antifreeze drain into a container.
3. Remove, drain and clean the antifreeze overflow bottle. Reinstall bottle.
4. Hook up a garden hose to the flush T and turn water on (not too high or you can damage seals/gaskets with the pressure). When water starts to run from the drain plug, start the engine and turn the heater on (make sure you leave the water running during this process).
5. When water runs clear (about 5 - 10 minutes), turn off car, then turn off water, and remove hose from T and cap it. Let remaining water run from drain plug. (Note: Not all of water will be drained out of system mainly the engine block. What I do is hook up a drain hose to the T connector, start engine and let the water pump push water out of the system. As soon as you see no water coming out turn engine off, remove drain hose and cap off T connector).
6. Close radiator drain plug and fill radiator with a 50-50 mix of antifreeze/distilled water (or buy premixed).
7. Start vehicle and bring to operating temperature to make sure thermostat opens. Add additional mixture as necessary until full.
8. Reinstall radiator cap.
9. Release any trapped air in cooling system by turning the plug on the top of the thermostat housing (be careful not to burn yourself). When only coolant (no air) flows from the plug, close it. You may have to repeat this several times to get all of the trapped air. Raising the front end of the car where the radiator is higher than the engine helps bleeding.
10. Add additional coolant as necessary. Also, fill overflow bottle to recommended level. Be careful not to open radiator cap if hot. You may have to do this several times.
11. Check for leaks.
12. Properly dispose of old antifreeze.

If I were to go ahead and replace the thermostat should I just get the same as it came with originally?

SInce you live in a cold weather state (Ohio), don't go below a 180 degree stat or you'll get little or no heat in the winter. If you're modded at all, a 180 is a good balance, if bone stock, stick with the OEM 195.