D9 406 V6 Exec Saloon STOP Warning, Temp gauge drops to zero

[cento16v]

Hi Guys

So the car has been great until recently i started getting the above message and problem, which of course means hot starting is a problem as it tries to flood as it thinks the coolant tempreture is low.

I have replaced the sensor, the message went and then all was ok, then on a longer run it happened again, the temp gauge dropped and STOP message appeared.

Im wondering if there may be an airlock in the system as very little fluid dripped out when i took the sensor out.

Is there a method to bleeding the cooling system? Its not on Autodata and i don't have an appropriate haynes manual for my car.

This is the only coolant temp sensor i believe there is on a D9 V6 looking at info from the coupe forum.

Thanks in advance,

Liam

[LouieMawr]

Don't think any air lock will be your problem but there should be a bleed point at the centre rear of the engine compartment on the hose from your heater matrix. A small cap, like what's on the tyre valves, take that off on either air or coolant should come out. It is almost the highest point of the cooling system. Give the radiator hose a quick squeeze until coolant does come out then recap it before releasing the radiator hose.
The small amount of coolant that came out when you replaced the sensor would be due to the system being a sealed one. If the expansion cap was off or the system was pressurised i.e. hot, the amount of coolant lost would have been more.

I'm not that familiar with your car but I might try pulling the sensor and dropping it, whilst still connected, into a cup of boiling water? To see if you can get a signal on your dash....

...Sorry.. all I've got at the moment

[cento16v]

Hi Louie

I pulled the sensor back out and no fluid came out again, i flushed the system and put new antifreeze and water in and everything is now fine, there seemed to be an air leak or blockage in the thermostat housing area for some reason.

Thanks for you help though

Thanks

Liam