so just got the new engine in about 200 miles ago and ever since its been put in. . I keep getting the coolant light turning on when im about 4500 RPM and holding that for a while. . .Then I take it down to 1000 RPM and it goes off. . . . Checked coolant level and its just fine. .

 

The float switch in the reservoir goes bad - common problem.

1 - Fix under warranty,
2 - buy whole new overflow bottle yourself or
3 - live with it.

 

my light was psycho before, but I just added a little distilled water in the coolant tank and the light never came back... hope this helps

 

+1....this has fixed most of them!

 

Sweet well ill show mazda when I got in on monday

 

mine does it too. 07. it also goes off if you wiggle the steering wheel dramatically like an old movie while doing over 35.

i'm living with it for now. probably get it fixed next oil change.

 

about how much distilled water?

 

I would try about 16oz. See if this makes any difference if it's too much it will go out the overflow like it's made to do.