Car running too cold??

[sade04]

Lately ive been getting very bad gas mileage (145-150 per tank) and the car had been taking FOREVER to heat up and most times it would never get up to the middle of the temp guage. then a few weeks ago i did a rad flush and changed my thermostat (stock temp). The car did warm up a little quicker and i did notice a little better mileage, although i couldnt tell for sure because i didnt finish off the whole tank before my thermo. housing started leaking. Everyone said that it would be a good idea to use MR. Gasket 180 so i went ahead with it. Now the temp needle will almost get to the middle then drop ALOT and stay below normal temp. and my gas mileage has gotten bad. So my question is, does the car run inefficient when its too cold causing excess gas consumption? Im going to switch back to the stock temp thermostat. Sorry for the long post. Thanks.

 

[Hoytster]

First of all, your engine shouldn't be running below the "normal temp" mark on your guage with a 180 thermostat. I would either suspect your temp. sending unit is bad or there's another problem.

The computer will richen the fuel mixture if it sees the engine isn't up to temp. My car was like this all winter due to a stuck thermostat. Not only was I getting bad gas mileage, but when I took my head's off I noticed my pistons were caked with carbon buildup (probably from the rich condition).

 

[sade04]

well the needle doesnt actually stay on the cold mark.

C [*ormal] H

The star marks where the needle usually stays, so i guess its in the normal range, but im used to it being right in the middle withing 15 minutes of starting the car during the winter. (like 3 minutes in the summer)
any other suggestions guys?

 

[HISSIN50]

Eric, you should get a real temp gauge before draing any huge conclusions.

Folks have used a piece of cardboard to block part of the radiator in really cold climates.

Good luck.