Engine Mechanical problem
1988 Mazda 323 4 cyl Front Wheel Drive Automatic 90 000 miles

Hi, my car seem to have a problem with the gage temp.
With the coming winter, the gage climb so slowly. If I let cold the engine for hours and then restart it and take immedialtly a highway, it will take so much time (15min at least) then if I start in the city (5-10min). I suspect on of my sensor's..but which ones.
My cooling system have been all flushed few months ago.
And what makes me piss off is the overdrive on my transmission who don't work until my bar gage temp climb just a lil bit before the middle...Sorry my poor english