Ford Fiesta Saloon 2004 - Overheating when heater turned to cold

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Wed 29 Jul 2015 14:47
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - rpmo
Car runs perfect when heater is turned to hot. Car boils up when heater turned to cold return to hot and car runs perfect again. Head gasket checked all ok. Heater blows hot and cold air. All pipes feel right. Any suggestions please
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Wed 29 Jul 2015 14:54
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - thunderbird

Blocked radiator. Failed thermostat.

Never seen a Fiesta saloon, all hatches in the UK.

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Wed 29 Jul 2015 15:00
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - rpmo
Hi yes sorry hatchback.
Radiator flushed, thermostat new, air locks cleared. Pressure tested. Still the same
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Wed 29 Jul 2015 15:14
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - Manatee

How long does it take to overheat (not that I am suggesting repeating the experiment too often)? i.e. is it just marginal or next to no cooling with the heater off?

Is it just in traffic that it overheats? i.e. is the fan not working when it should (the fan isn't usually needed if you are bowling along at a reasonable rate with the airflow over the radiator).

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Wed 29 Jul 2015 16:19
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - rpmo
Any distance so far between 10 and 75 miles, fan works, can stay running stationary for over two hours. Garage are at a loss so am I. So many thanks for any suggestions
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Wed 29 Jul 2015 17:19
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - elekie&a/c doctor
Sounds like a flow problem.could be water pump (impellor loose)or a partially blocked rad.Pull the rad out and lay it flat, block one end ,then fill it with hot water .Then feel if you have any cool spots.
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Wed 29 Jul 2015 20:01
Ford Fiesta Saloon 2004 - Overheating when heater turned to cold - rpmo
Many thanks will give rad a try. Garage did flush it and say it was ok but it's got to be something so I will give it a go in the next few days
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