Re: 98 overheating problem

I have a 98 Cavy. It only gets really hot when I'm in major stop and go traffic. I then turn on the defrost, it cools down. Problem solved temporarily. I know I need to flush out the coolant system. I had a friend of mine replace the upper hose and put in a new thermostat. We did not flush out the system. Just drained out the coolant. It looked like sh%^. For about 4-5 days it stayed under the halfway point on the temperature guage. That's pretty strange for my car. Then it started again today. My car never actually gets into the red zone. It gets close, but never close enough that I have to stop. Any advice?? I thought it might be the temp sensor, since the fan still works. Any advice would be appreciated.

I forgot one more thing, I don't know a great deal about cars. They had 3 choices of thermastats. 160, that's for high performance cars(which mine is not,)181-190, 200+. I got the 181-190. Could this be a problem???

Anyone???

Why did you change the hose and thermostat?
The car was getting hot?
1.- Is the coolant level normal? check this first.
2.- Flush the system.
3.- Another thing is that maybe your new thermostat is not letting the water go through, sometimes new thermostats are defective, if you want you can eliminate the thermostat.

Why did you change the hose and thermostat?
The car was getting hot?
1.- Is the coolant level normal? check this first.
2.- Flush the system.
3.- Another thing is that maybe your new thermostat is not letting the water go through, sometimes new thermostats are defective, if you want you can eliminate the thermostat.
Thanks for the reply. I changed the hose and the thermostat because, my car has almost 98,000 miles. I've only changed the thermostat once at 15,000, due to the same problem. It's never been flushed ,ect. Yes, the coolant level is normal. I don't know about the thermostat being defective. The minor repairs I had done made the car run extra cool for about 4-5 days. It only heats up above normal after stop and go traffic(construction,delays,ect.) I could get on the highway 2-3 hours and have no problems. Another good friend of mine told me his friend has a 98 Blazer. It has the same problem as my car. He switched out the Dex-cool, and replaced it with regular antifreeze. He's never had a problem since. So I don't know. Thanks for the input.

I think that flushing the system is the answer, do the complete work, flush the old Dex-cool, remember to fill the radiator again with water and put a cleaning additive ( prestone has one, but I don´t remember the name), run your engine again, this will be a best flush method, then take out the radiator and clean it up with plenty water, put it back in again and add the coolant and the water, remember to run the car to get the coolant in the system and avoid to have a bubble of air in the system.
I hope that this will work.