I just had my rad and thermostat replaced.

Prior, it was running about 1/4 - 1/3 on the guage with AC on in heavy traffic, idling, etc., and getting really bad (10) mpg.

Now, it's running 1/2 - 2/3, sometimes 3/4 on the guage but I just filled up and the mpg zoomed to 17+, same diving patterns.

Should I be concerned with the temp?

Thanks guys, ya'll have been lifesavers.

 

NO, I do not think so. the problem was the the thermostat was probably wide open and the car never warmed up. So the Ecu was still thinking the engine was stil in cold start cycle And running a little rich which would make the gas mileage suck

 

2/3 guage is not NOT good. S5's I hear read 1/2 guage at normal temps. But he has an 88 vert and they sit at 1/4 or 1/3. Mine does and I get 300 miles to a full tank that runs up to about 19 or 20 MPG

 

what year of car is this?
if its 86 to 88 1/2 - 2/3, sometimes 3/4 is way to high.
if its 89 to 91 its about right but still seems a little high.
did a mazda stat get installed of a jobber one?

matt

 

thanks guys... sorry, brain dead (me) 88 vert