I started having the same problem, driving at 7-9k for a few minutes the light would come on.

I think the water temps were around 90 deg c, maybe 94. (backing off brought it quickly down to high 80s).

So maybe the sensor doesn't work properly when its hot?

 

No, I think it just wears out.

I did experiment this weekend, so see this thread............ https://www.rx8club.com/series-i-trouble-shooting-95/coolant-bottle-greatest-secrets-revealed-182793/



It seems they are onto "M" series coolant bottles.
The part number is: N3H1-15-350M.
Make sure you get the "M" revision!

 

Think I got this figured out.. light came back again.. when the car's off(cold) or idling (warm), the coolant level is a bit over the full mark, however, as soon as I step on the gas, it dips well below the full line (3-4k RPMs) so it would make sense that at even higher RPMs on the highway, it may drop even more and then cause the light to come on because there isn't much coolant in the tank.

 

While I agree with you...................be prepared as most of us have seen it come back on, be more frequent, and eventually be on all the time.

Little more info for you when the time comes:

https://www.rx8club.com/showthread.php?t=182793

 

i am proud to say that i am one of the lucky ones with the m-series tank no probs so far.

 

Over the weekend, on the caravan drive up to SevenStock, I saw the "Grey Poupon" light up right as we all revv'd up good to enter the freeway, then itwent out about 10 minutes later, then it went on and off while we were at a stable cruising speed in 6th gear all the way up for the next hour....But on the ride back Sunday, the light didn't go off at all. Hmmm.

 

Ignorance is blissssssss!!!!!


Yea I know it'll most likely (ok. it will.) come back, but I can hope


Don't burst my bubble man! The car's still new!


Hehe..