My coolant light comes even though it's full, but only when I race my engine

 

A bad sensor can indicate a false low level.

Try topping right up with coolant, or get it 'dealered'.

Mine shows low at 90 mph, no matter how full it is.....

 

Keep an eye. Although I don't race, mine began to appear at high speeds, then did it no matter how fast or slow you drive. My 8 is 2004. In my case, and I have seen the same in other posts, I ended up changing the coolant reservoir. It has a sensor inside, at one of its side, that there is no chance to change it so you have to change the reservoir. Should be between $150 to $200. If DIY, watch out with a short hose the reservoir has at the back (called the overflow hose) since it is very easy to brake its conection to the plastic radiator cover.

 

yeah at higher speeds or racing my light comes on, but usually turns off within 5 or 10 seconds...in the manual i think it says that if the light stays on then to immediatly pull over, let your car cool down.

 

under heavy throttle mine has just started coming on... half a minute to a few minutes and then goes out. Coolant level checked and fine. I think it is a bad sensor as mentioned above and will have to go to the dealer.

 

Once or twice:

Only when I go too fast around corners. The fluid has a tendency to force its way out.

One time I was missing the resovouir nut. Check the botle make sure it is tight.

 

Coolant level should be checked with cold engine. Level should be near reservoir "F" line.

 

top up solved this for me - was coming on at high cruising speeds (80MPH plus)

 

yup. Comes on when I'm doing my sunday drives all the time. I get it up above 4K for a length of time and the light comes on until i shift into neutral and let the revs drop to 2K for a few seconds. Gotta send it in for warranty work to fix that.

 

What do you all top off with?

 

I go to the dealership and they top me up with FL-22 no charge.

Owners manual says don't use anything else.