hi guys have a question about my focus. its a 2004 1.6 flyte. the cooling fan seems to come alot on it. even when starting from cold its on within a few minutes. is this normal. when i turn the car of theres also a hissing coming from the expanion tank. an advice would be great as i dont ant to end up with a big problem.

thanks.

[quote name='milky' date='06 August 2010 - 11:15 PM' timestamp='1281132312' post='91706']
hi guys have a question about my focus. its a 2004 1.6 flyte. the cooling fan seems to come alot on it. even when starting from cold its on within a few minutes. is this normal. when i turn the car of theres also a hissing coming from the expanion tank. an advice would be great as i dont ant to end up with a big problem.

thanks.
[/quote]

sounds like the CHT (cylinder head temperature) sensor needs replacing.

£21 plus the vat (in the uk)

shouldnt be any hissing coming from the cap?

does the temp gauge go over halfway in the instument panel?

sounds like the thermostat is stuck shut..causes the engine to overheat and boil the coolant.

1 change the coolant cap
2 change the thermostat
3 change the cht sensor if the gauge is acting up.

[quote name='jonboy01' date='07 August 2010 - 12:32 AM' timestamp='1281136929' post='91713']
does the temp gauge go over halfway in the instument panel?

sounds like the thermostat is stuck shut..causes the engine to overheat and boil the coolant.

1 change the coolant cap
2 change the thermostat
3 change the cht sensor if the gauge is acting up.
[/quote]

problem being the focus gauge doesnt really move even when the engine is very hot so its not a great indication.
it could be the thermostat but the CHT is also common for the fan coming on all the time

[quote name='stef123' date='07 August 2010 - 12:37 AM' timestamp='1281137258' post='91714']
problem being the focus gauge doesnt really move even when the engine is very hot so its not a great indication.
it could be the thermostat but the CHT is also common for the fan coming on all the time
[/quote]

if you have aircon it will be on a lot even when you think the aircons switched off its not you need to change the dial to say blow at the floor for it to switch off

You may find the pressure cap on the expansion tank is goosed. If it is the cooling system cannot pressurise properly and the coolant will heat up faster, kicking in the fan sooner than it should and more often.
Hopefully you are not getting the coolant/air actually bubbling up through the expansion tank?

Rob

[quote name='Madrab' date='08 August 2010 - 12:37 AM' timestamp='1281223623' post='91869']
You may find the pressure cap on the expansion tank is goosed. If it is the cooling system cannot pressurise properly and the coolant will heat up faster, kicking in the fan sooner than it should and more often.
Hopefully you are not getting the coolant/air actually bubbling up through the expansion tank?

Rob
[/quote]

after reading the post properly sorry was knackered you said hissing so i agree with madrab it sounds like you need to get a new pressure cap its either not hiolding pressure ie top rad hose is soft or its overpressurising top hose is hard not holding can be as simple as the cap over pressuring can be down to a faulty cap in the best case or head gasket in the worse