I've got a 1995 civic with the 1.5L and it is running cold. About 3000 miles ago I had the head gasket replaced. After that job was complete I noticed that my fuel milage had dropped from 38 mpg to around 30-33 mpg and that the engine temp barely raised above the first mark on the guage. (For 309,000 miles it ran about 1/3 of the way up the guage)

I replaced the thermostat hoping that would be a fix, but it didin't. I just finished driving the car home from a 500 mile trip at 75 mph and the engine temp only raised to normal one time and that was when I was when trafic on the interstate stopped going up a mountain. Also, I know it running cold because of the outside temp. It was 70 here in NC today and the car temp didn't rise.

Any help or suggestions woudl be great before I take it to the shop.

 

The only thing that will cause this is the thermostat not closing fully. The new one seems to be bad. Also you want the 185 degree one.

 

I'm going to swing by the Honda dealer and pick up a new thermostat and see if that helps.

 

I replaced the thermostat and no change. One thing I notice is the hose leaving the radiator is cold and the one going to it is very hot. The hoses going to the heater core are also hot.