Hey everyone. I have a 2003 Honda civic Si 2 door coupe with 132,000 kms on it. My problem is that I cannot get the car to get up to the normal running temperature with my blower on high. If I leave the blower off, or on low setting, and drive the car, it will get to the normal running temperature, and blow very little hot air. When I turn the blower up higher to get more warm air, the temperature gauge in my car starts slowly dropping towards the "C" mark on the gauge and the car will blow out cold air. I replaced the temperature sensor, and the thermostat, but neither solved my problem. I took it to 2 honda dealers, and they both told me the only thing they could say was not to turn the blower on high! USELESS> this will be the last honda I buy. Can someone please help me figure this out. I live in canada and the days are very cold! Please help. Thanks.
P.S. The antifreeze is not leaking and is still at the normal level

Restrict the airflow through the radiator, by carefully rigging a plastic radiator cover (winter front). You may have to experiment with what's the proper size--better yet, make it adjustable. This is not an uncommon problem, during the winter, on some vehicles. I'm sure you have seen folding mechanical radiator covers on some delivery trucks. Your heater core, when the blower is turned on high, is acting like an efficient radiator and dropping the engine temperature too much. Therefore, I don't really think anything is wrong, per se, with your car. This should also improve your vehicle's performance and gas mileage, during the winter.

You'll like these pictures:

Winter fronts from Alaska Tent and Tarp (http://www.alaskatent.com/products/covers/winter_fronts.htm)

If you aren't already, use synthetic engine oil and synthetic transmission fluid in your Civic. It's the only way to go, in extreme cold or heat.

Now, take back what you said about Hondas.

Hey, thank you very much for the response. If that is all that is wrong with my car, how come none of the honda dealers were able to tell me that? Also, it just doesn't make sense to me that the blower will not push out hot air in the winter time. Isn't that what it's made for? It never acted like this any other winter. Just this one. I am sorry for my ignorance with cars, I don't know very much, and I am not saying you are wrong, I am just wondering why thais is the first winter this would happen and why my heater, which I would think is made to blow hot air in the winter, will not. Please... and I will not take back what I said about hondas. I have had nothing but trouble with this car since I bought it brand new. I have already replaced numerous parts such as the thermostat housing gasket, the head gasket itself... and more. And I never drive my vehicles hard.

Let us know the solution to your problem.

Still no answer. I had an error with a TPS sensor the other day. Could this have anything to do with this problem?