some camera's have to many filters over the sensor and washes out certain colors. like older pocket digi cams can't handle purple, it comes out blue, due to the UV in it, the color is always messed up.
white balance is the next thing, make sure its not on auto, use shadow or i heard if you use a custom white to shoot something slightly blue, it will enhance reds. its good for autumn shots where you don't want to do a lot of editing.
it could be that your camera is dying.
if you have raw, shoot in that and just edit it back.
do you have a sky filter on it? maybe the tint of that is throwing the camera off? and do other colors look odd? purple, green, etc? how about a range of red, like a gradient or different shades on a chart?