Hi


The fan blows cold air when stationary, and blows hot air only when driving, although not all the time. I have checked coolant level which was very low. This has been topped up but the problem still exists.


The fluid level has never dropped until recently.
No white smoke
Temp gauge is where it should be.
It has been mentioned the hoses can sometimes leak. I have ran my hands along these and are bone dry.


The engine under tray has water on it but it has been raining recently.


Any ideas what I should be looking for.

 

Replace the thermostat. It is a maintenance item anyway so your not wasting time or money replacing it. 90% probability that is the thermostat. Unless your cooling system is very rusty. Then it could be a partially plugged heater core and or a blade rusted off the water pump impeller.

 

Unfortunately you didn't mention how old your vehicle is or mileage. Fluid must be changed approx every 3 years, otherwise you may have clogging, rust issues. Changing the thermostat is a great suggestion.

 

Hi
Update on this issue
Car is a 2007 model with 75k on the clock


The header tank was full
Local garage had a look for any leaks non found


They took of the pressure cap (on radiator) and filled it from there and since then its been fine.


They told me although the header tank is full sometimes you can get an air pocket at the top of the radiator.

 

If coolant is missing then it has a leak. Water pumps are notorious for leaking when cold (overnight) and sealing up when the engine warms up. The coolant can't be sucked out of the recovery tank if the system has a leak. Place a large piece of cardboard under the engine when you park it overnight and check it in the morning.