Coolant Warning Light coming on again when coolant level is not low on 2001 Buick Regal

I rencently purchased this auto (used) with only 24,000 miles on it, has been garaged kept all it's life. 3 days ago the low coolant light came on, I immediately filled the resivoir up (it was very low). Now 3 days later the light is coming on and the coolant is not low at all. What could be wrong?

by in San Antonio, TX on August 15, 2009
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2 answers
ANSWER by , August 15, 2009
Hey SG, it's probably the level sensor in the coolant reservoir sticking. Try smacking the reservoir a couple times and see if the light goes off, or look inside the reservoir at the sensor and see if it is stuck. Even if you fix it, it may be a temporary, they tend to continue to get stuck. Good Luck!
ANSWER by , August 24, 2009
Hi SG. I have a 1998 Regal and a family member has a 2001 Regal, both 3.8L and we both have the same problem. The low coolant level light comes on and off at times even though the coolant level is full. Both cars have been checked out and are fine. Most likely the sensors start reading falsely after a period of time. I've been ignoring the low coolant level light and just check the level manually at regular intervals. If you do decide to replace the sensor yourself, it is located about halfway down the radiator on the passenger side. Good Luck.