Thermostat question
 

I have a 95 civic ex with the d16z6. My thermostat is currently stuck shut and I hope thats all thats wrong with it. My question is when I change it out would a hotter thermostat make a noticable difference in FE? I've read that a 190 degree thermostat is better for FE but I don't want to push the head gasket any at all as my car has 240,000 miles.

the savings in FE would be very small compared to the loss of the engine. imho

I went with a VX thermostat on my high-mileage Civic. Slightly hotter, but obviously a Honda-approved temp. Partsgeek has NTC (OEM) thermostats cheaper than the dealer.

Does your head gasket leak already?

It boils over into the overflow then evaporates. It uses a little coolant every day.

That isn't a head gasket leak, that is a result of your engine already running too hot since the thermostat is stuck shut.

Your risk of blowing the head gasket is many times greater with your current problem than by running a 190 degree thermostat.

I'm no expert on the subject, but I can't see any reason why a 190 degree thermostat would appreciably affect gasket deterioration. There is practically no added pressure since it isn't a boiling temperature. Perhaps the material is slightly weakened by the extra heat, but it should be built to withstand much higher temps.

I replaced the stat already but im wondering if its a bad one. I will swap it out again and make sure the next one works before I put it in. Is there a certain autozone stat thats better than others? I know original honda parts are the best but I need a quick fix till I can get an oem one from honda.

You can check the t-stat by feeling the radiator hose. If the upper hose is warm to the touch after you've been driving a while, then the t-stat is open. If it's cold all the time, the t-stat is closed.

-soD

You should also see the temp gauge go up if the t-stat is stuck closed. I've always purchased the cheapest t-stat I can find and haven't had any problems.

It is unlikely that you had 2 bad t-stats in a row that stuck shut, but I suppose it's possible.

Do you mean the lower hose? Before the lower hose was cool and the top was hot. Now they are both hot. I'm wondering if the lower is hot from the temp under the hood. Its. It's not as hot as the upper is. Also would a stuck stat cause the fan not to come on? I haven't seen it come on yet since I've been driving the car. The sensor is right after the stat correct? So if its closed then it wouldn't know when to come on?