Yesterday my coolant buzzer came on after I sat still with the car running for like 3-4mins and then driving away for like 1/8mile. Temperature gauge was reading normal temperature. I opened the filler cap and the coolant was filled up to where I last checked it (long ago). Then I also opened the AST cap and heard a vacuum being released. I closed both caps and fired her up - no problems now. I drove home to add some distilled water but it would just come out of the AST if I opened it (so obviously it was full).

I then went for a drive for like 30miles without a problem.

What could it be ? It was very cold last few weeks around here and I havent started the car for like 3weeks. Could it be there was some air in the system ? I changed the thermostat 3k miles back, also the main radiator hoses and Koyo radiator, also RX7.com AST.

I hope its not the o-ring thing...

 

One thing I may add - when I opened the filler cap, the level of the coolant was fluctuating a bit - from full up to down to 1inch or a bit more from the top. I find it strange...

 

Don't worry. It happened to me once in the past while the car was cold the buzzer came on. I switched off the car, checked the coolant, and restarted the car and it was fine. Never happened since then.

 

same thing happened to me a few weeks back. prolly just a bubble in the system. I have had no problems since.

 

Cool, thanks

 

yea mine came on for like 30 seconds last week. It was a cold morning. temps were fine. It hasn't happened since. Don't be woried.

 

it's normal..