Ford Focus (1998 - 2004) - 2000 1.8 Temp gauge into red, fan running constant

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Fri 15 Aug 2008 17:27
2000 1.8 Temp gauge into red, fan running constant - bigdynamike
Hi All,

This is my first post on this forum but I've read through many in my search for suggestions to an "overheating" problem with my petrol Focus. Last night on the way home from work the temperature gauge shot into the red and I had to pull over several times, switch off the engine and wait for it to cool before proceeding.

A wee bit of background. Over the last week I've noticed that the heater is not blowing hot air (we've had some uncharacteristically mild days up in Scoltand so unusally not had the need for heat!). The fan has also been kicking in more often than usual and for the last couple of days it has been on constantly for the hour long, 10 mile commute across town. Then as I mentioned the temp gauge went to red.

My knowledge of car engines (especially for anything controlled by ecu's) is very limited but I'm willing to learn. Any suggestions on checks I can undertake and signs to look out for to determine the cause of the problem and possible fixes would be appreciated.

In other posts (mikej, same car, similar problem without the "broken" heater factor) I picked up references to head gaskets, radiator blockage, coolant factors, temp thermostat but to be honest I don't know where to start.

Any help appreciated.

Many thanks
Mike (H)
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Fri 15 Aug 2008 18:08
2000 1.8 Temp gauge into red, fan running constant - RichieW
It could be as simple as a thermostat stuck shut.

If it is, the radiator won't get warm as the water won't be circulating so it heats up around the water jacket around the engine cylinders and stays there till it boils.

Let the engine run for a few minutes until the water temperature rises. The top radiator hose should get warm as the thermostat opens and fills the radiator with hot water for the fan to cool. If the radiator hose stays cool then the thermostat is stuck shut.

Most ford thermostats open at about 88 to 90 degrees.

A more complicated cause would be a failed water pump. The water wouldn't circulate and so the engine would overheat. Its a bit more complicated to troubleshoot though so start with the thermostat.
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Fri 15 Aug 2008 18:35
2000 1.8 Temp gauge into red, fan running constant - Screwloose
Mike

Have you actually checked the water level?
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Mon 18 Aug 2008 10:53
2000 1.8 Temp gauge into red, fan running constant - bigdynamike
I didn't even check the water level before as the car was only serviced a month ago - idiot that I am.

I did check the levels over the weekend and as predicted they were very low, so I topped up and ran the engine until it reached normal temp. The heater started working again and temp remained stable.

However after 10 mins I checked under the car and liquid was pouring out from what appeared to be the engine block, although it could be from a hose - difficult to tell. So the problem was the water level and a leak somewhere in the coolant system.

The car is being MOT'd today so I've asked them to check for signs of leakage.

Thanks for the replies.
Mike.
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Mon 18 Aug 2008 13:09
2000 1.8 Temp gauge into red, fan running constant - Waino
Trouble is, a car can go for years and years and the water level won't change - then, when there's a sudden failure, it can drop like a stone.

As I learned when the HG failed on the Mondy, if there's a sudden rise in engine temperature and the heater fails (fortunately, I noticed mine 'cos it was winter!) - the thing to do is to pull over straight away and check the water level. I was lucky and caught it before the engine fried.
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Mon 18 Aug 2008 14:34
2000 1.8 Temp gauge into red, fan running constant - Screwloose
Mike

I've seen a lot of corroded core plugs on those; that could be one possibility.
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