92 Integra overheating, troubleshooting

This is my son's car. We replaced the radiator about 6 weeks ago. Not sure that has anything to do with the current problem. A few weeks ago, he told me it was overheating in stop-and-go city traffic but ran at normal temperature during open highway driving. My first thought was a fan problem, since the fans should kick on in stop-and-go city traffic.

My son says the car now seems to be running hotter than normal more often, but still runs at normal temps during open highway driving.

Other than verifing that fans are working properly and that the coolant level is adequate, the only the other thing I can think of is the thermostat. Does this behavior sound like a thermostat gradually getting worse? My experience with bad thermostats is where a car will not warm up to normal operating temperature during winter months here in Ohio. So, I'm wondering whether the thermostat might be the cause in this case?

why did u replace the radiator? it could have overheated and blew the head gasket.

is the upper radiator hose hot or cold during normal operating temps?

My experience with bad thermostats is where a car will not warm up to normal operating temperature during winter months here in Ohio. So, I'm wondering whether the thermostat might be the cause in this case?

usually a thermostat will go bad in one of two ways. It will either get stuck open and not let the car warm up as you mentioned or it will get stuck closed and not let it cool off therefore causing overheating.


However if it cools down during highway driving but not in city driving I would check the fan and the fan switch.

The thermostats in our cars are designed to fail in the open position, just another reflection of good Honda engineering. Anyhow if it was over heating ie: it went really far to the right on the gauge then it is not the thermostat. But if it was just rising when stoped and then cooling back off again while driving then it would be either the coolant level or the thermostat.

usually a thermostat will go bad in one of two ways. It will either get stuck open and not let the car warm up as you mentioned or it will get stuck closed and not let it cool off therefore causing overheating.


However if it cools down during highway driving but not in city driving I would check the fan and the fan switch.

Thanks for your comment. I rode with my son Tuesday evening during some city driving. I noticed that when he came to a stop light and had to wait for the light to change, the temperature would rise by the time the street light changed to green. Then, soon after getting back in motion, the temperature would drop, obviously due to the cooling effect of air movement through the radiator.

I believe this is a clear sign that the fans are not operating properly.

... But if it was just rising when stoped and then cooling back off again while driving then it would be either the coolant level or the thermostat.

Nope, I think you're wrong there. As stated in the previous post, that behavior most likely indicates a problem with fan operation.

Nope, I think you're wrong there. As stated in the previous post, that behavior most likely indicates a problem with fan operation.
Sorry buddy but I am right:smokin:
Let me school you for a moment :biggrin:
When you haave a faulty thermostat it is open all the time, which will prevent the coolant from transfering the heat correctly. A thermostat in a car does not just open and stay open after the car warms up it closes and opens depending on the coolant temp. Just trust me if the motor is not over heating than it is the thermostat. The exact problem you described is what caused me to replace my thermostat. By all means still check the fans but I think you will find that it is the thermostat.

If you want to test the fans you can start the car and have someone hold the throttle at about 3k until they either come on or the temp gauge reads on the greater side of the half way point.


I have been doing this for quite a while so I know what I am talking about, as most of the regulars here could tell you. ;)

I have been doing this for quite a while so I know what I am talking about, as most of the regulars here could tell you. ;)


Yeah i'm gonna have to agree with him on that one.


I've been a member for a long time and I'd have to say that I have yet to meet someone who could go head to head with Whtteg on integra knowledge.





PS: Whtteg sorry about those tuts I offered to write, I got swamped after I offered and never got to them. I will get to them eventually though.