Why is there no indication to warn of no coolant

Hi,
I have a 2001 civic. The water pump leaked and all the coolant came
out. After driving it for a while the engine melted, surprise. the
thing is, there was no indication on the temp gauge of overheating and
there was no warning of any kind that the coolant was empty. shouldn't
there have been at least a check engine light warning. Why didn't the
temp gauge go up?
thanks

 

Your sensor may have been faulty before the leak. Usually the temp gauge
would rise. I would also guess a red light would appear on the dash (not
sure what lights are on the civic dash).

 

If the coolant was slowly leaking, the smell of antifreeze should have
told you to check the coolant. Also, before all off the coolant leaked
out, the temperature gauge should have been crawling up.

 

Most cars do not have coolant *level* sensors, so no warning about
coolant missing. Furthermore, the coolant *temperature* sensor measures
just that, coolant temperature. When it is not immersed in coolant it
will not necessarily track engine temperature.

It is a bummer, I wish the warning system would be a bit more
comprehensive. Same issue with the oil pressure warning. You only get
the warning after the oil pressure has dropped, no warning about the oil
level being to low.

Some cars have coolant level alarms (VW etc.) and I have seen cars with
oil level alarms (Renault Megane, Fiat Chroma from the early 80's).

 

To prove this I'd boiled a sensors and compared to a sensor
under a propane torch. The torched sensor did not register
change in resistance. Instead, it melted.

But since the coolant sensor is place half up it should register an
overheating when the coolant is half full. It appears the coolant
escape quickly. Putting this into mind, whenever you loose an
ounce of horsepower, you are overheating. Train your mind for
these subtle differences.

 

One of my former Civics lost its coolant and the temperature gauge shot up
all the way - that's how I knew. The fact your gauge may have been faulty
and didn't alert you to trouble (where you would, of course, shut off the
engine and have the car towed to a service center) might give you some
recourse for your melted engine.