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Discussion Starter #1
So I have been reading on some other sites that if the coolant is to low it will actually decrease the gas mileage. So I took some readings and found that my operating temp was 145-160F. I switched to a new thermostat and now I am running 190-195F. With the lower readings I was getting 45+ mpg, with the new thermostat I can barely get above 35 mpg.....WTH?

Any help or advice?

Oh yeah, drained, flushed and refilled with G12.
 

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I think it might be something else going on there, I can't see the thermostat causing that much of a variation in mpg's. Even if the low coolant was going to decrease mpg's I wouldn't have thought it'd be that much, maybe 3-4 mpg. It just don't add up:D
 

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Discussion Starter #4
This is exactly was I was thinking....

I used Torque with my droid to check both before and after mpg tests. I will try it for another week or so before I make a decision, and test it against my odometer and volume of next fill up...Its just that everything I have read says that it should increase not decrease and the warmer months it should increase as well....

Grrrrrr
 

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Discussion Starter #5
First one is when halfway to work. Not sure why it is better, but it is....



This one is after I pulled into work. MPG is better, much better than the weekend. However, is it due to the elevation changes???

 

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? Those mpg readings are good. As a side note, don't lug the engine at that altitude. The thin air + high load at low rpm isn't good for the turbo because it can cause stalling of the turbine.
 
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