Ford Fiesta - Ford Fiesta 1999 T 1.25 zetec s heater always hot

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Thu 12 Aug 2010 20:54
Ford Fiesta - Ford Fiesta 1999 T 1.25 zetec s heater always hot - chlojosh

Hi, i had an issue with my fiesta recently, it was randomly over heating, and the temperature of the heater inside the car was also whatever it decided to be at the time, i wasn't losing coolant or oil, and both were clean from one another. Some times i could do 100 miles trouble free and another i'd do 5 miles and the temp gauge would hit red and coolant would be bubbling away.

I changed the thermostat £9, flushed the system, and re-filled the coolant £10 and that never fixed the problem.

I read on here a couple of people had got my very issue with random over heating and they said to change the heater control unit as when broken (common problem) it can cause the engine to over heat. £19 later all was spot on, done 200 miles trouble free and the heater inside the car has been working good too.

My problem now is today on the trip home from work, with heater on cold and and engine temp at it's normal mid point, there was heat coming through the vents, some times luke warm then cold then warm. Could it be air in the coolant system????

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Fri 13 Aug 2010 03:09
Ford Fiesta - Ford Fiesta 1999 T 1.25 zetec s heater always hot - Collos25

To check if there is air in the system let it run without the expansion chamber cap when it reaches temp and the stat opens any air will be expelled but air has to come from somewhere bearing in mind its run ok for such a long time, I would have thought there is another problem.

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Wed 1 Sep 2010 17:33
Ford Fiesta - Ford Fiesta 1999 T 1.25 zetec s heater always hot - chlojosh

still running hot, like the heater is on full blast.

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Thu 2 Sep 2010 15:54
Ford Fiesta - Ford Fiesta 1999 T 1.25 zetec s heater always hot - tdc

Mine`s been doing the same.Previous owner replaced the plastic-degraded heater control unit in the bulkhead recess and didn`t purge the system of air .They released the expansion tank cap when hot several times to get the temp gauge reading normal(not recommended unless you really know what you`re doing!)

I take possession of said vehicle and all is well for a couple of thousand miles until one day tootling along at sixty on a B-road half-way into my 30-mile journey home there was a horrible burnt plastic smell.I half expected to see flames come out of the dash and suspected an electrical fire.Then 3mins later I was hit with a wave of intense heat from the vents.

I have had to drive around with the heating stuck on full with windows wound down ever since.....until my brakes failed(also not recommended)the other day.No connection with the HCV obviously!

As for the heater control valve I suspect a cheapo faulty new one was fitted....it was bought off ebay for about £15 instead of £20 for OE.You pays your money and someone else pays the price!

Now,can anyone answer my post on Fiesta metal brake pipes...please?

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