computertom

After not driving my 09 C63 for about 12 rather cold days, when I eagerly jumped back in it, boom, low coolant warning. That's odd I thought. So I checked the tank. Tons of coolant, right where it always is. Checked the oil. All good, right as it should be.

So yeah, the thing is, I replaced the bolts with updated bolts and a host of other pieces parts a few months ago.

Marked the coolant level. Started it (So nice, I missed it), and went to the gas station. Warning went away shortly after starting it. I did not hit "ok".

Brought it home. Let it cool over night. Coolant at exactly the same level.

Started it this am. Warning. That shortly went away. Drove it to work. Let it cool all day. It was COLD. Coolant dead on the line still.

So, do these sensors ever go? How high in the reservoir should it be to not trigger this? It's about 3/4 inches from the top.

Anyway, thanks for any tips. And no, I don't need to read the long threads about head bolts. Been there, done that, upgraded the motor.

Thanks,
Tom

computertom

Update: checked the coolant this am, when is was a brisk 13 degrees Farenheit, and it actually seemed to be up about a milimeter or two over the tape and line I added.

Confused. Car is running well, exhaust looks fine (for a brutally cold day).

mbcomer

Add some coolant, see if the warning on startup goes away, and monitor?

Sounds very doubtful that you have a real problem, possibly just a flaky sensor.

computertom

Coolant added. We'll see how we look in the am. Not too worried about it being a big deal (since the head bolts are already done).