Engine Warm-Up

Ah, I might have something.

One fellow in this discussion (Mondeo owner discussion club) tells us the car has two thermostats (one for engine oil, one for coolant). Have you checked them both?

You have thermostatically controlled fan, I would check to make sure it isn't staying on all the time....the fan relays go bad.....

http://www.fixya.com/cars/t4079696-ford_mondeo_fan_comes_nearly_all_time

http://www.talkford.com/topic/131243-radiator-fan-wont-stop-at-all/

I have no idea why they would say to put an electric heater in the stat but-

when thermostats fail they usually (but not in all cases) fail in the open position. This isn't bad since what would you rather have- a cold or cool interior of the car or an overheated car with whatever damage accompanied that problem (use your imagination up to and including a seized engine). When the thermostat fails open it takes the engine much longer to get up to normal temp since the water is circulating much faster through the engine which would delay the heating. I have experienced this numerous times with failed thermostats. Usually if you are going to take things apart to get to the thermostat your might as well replace it while you have it apart. New ones usually last longer than old or questionable ones.

Another possibility, I'm not familiar with your car, is that if the dampers are vacuum controlled there could be a restriction or loose hose on the driver's side damper control. (For those unfamiliar the damper is the "valve" in the air passage that opens to let the air go from the heater to the interior).

Good Luck, Old Salt

I saw the same behaviour on an older Saturn Sl2. After replacing the thermostat, the new thermostat reached operating temperature much faster as revealed by a data scan tool. In addition, when dropping the old thermostat and the new thermostat in a pot of boiling water, 2 things were evident: 1) the new thermostat closed more quickly and 2) the new thermostat closed completely whereas the old thermostat was "lazy" and never closed tightly - allowing some leakage in addition to the small bleed hole. To summarize: With the old thermostat, the engine only reached 180 F (82 C) while the new thermostat allowed the engine to reach 195 F (90 C). This was especially noticeable at idle where things occur more slowly due to lower heat load from the engine.

It sounds like the thermostat is stuck partially open - probably in approximately the position it would sit after warm up

An 8 year-old Mondeo. About right for a replacement thermostat.

An electric heater for the thermostat - ?

The only heaters for warm-up that I am familiar with are the block heaters that are usually specified for Scandinavian countries.

Several manufacturers put extra electric heaters in the cooling water somewhere to heat up engines quicker that would otherwise be slow to warm up in winter, good diesel engines usually. This is so that the screen can be quickly ice free and the passengers too!

It is probably only about 0.1 Ohm or so, big currents.

The best way that I know to know to find out if one is fitted is, for instance with VW Diesel engines, is to check the alternator, with VW, if it is 120 amps or more in size, then there is a strong likelihood that the extra water heater is fitted. It is only switched on once the engine is actually running, not before....

With VW cars, the usage is fully automatic depending upon the water temperature being below 10 degrees C or so.

With my Mitsubishi with a 2 Liter VW Diesel engine, there is a switch marked "Heat" to allow the heater to be controlled by the driver, but it also has a thermostat to turn it off when the water reaches operating temperature. In winter I leave it switched on all the time.

It would appear that Ford uses a similar system (Citation needed!)

You know what the problem is so just change the stat, there isn't anything else it can be, or stick a piece of cardboard in front of the rad.

Bazzer

Thanks to everybody who's commented.

I should have said it's a petrol model. The book refers to a booster heater on some diesel models, but just to add extra heat, whereas on petrol the implication is that it affects the thermostat in some way. The actual words are "Unusually, the thermostat is fitted with an ECU-controlled heating element, to reduce warm-up times when the engine is started from cold - when the coolant reaches a certain temperature, the element cuts out."

Still can't see how it does that, but I think there's a good bet the posts that said it's the stat not fully closing have nailed the problem. I'll find out when I change it.

Thanks again

Generally you have a large low resistance electrical heating element in the water jacket somewhere.

This is fed with 12 volts from a heavy duty alternator once the engine is running only, probably taking more than a Kilowatt from the alternator.

It therefore increases the mechanical load on the engine when switched on by low water temperature, which burns more fuel and warms up the engine quicker.

Also the heating element heats up the water at the same time till a specified water temperature is reached.

It makes driving such fitted cars far nicer in areas of low temperature.....simple but effective.

I cannot promise you that the Ford has a similar system or not, you will need to ask Ford that...but it certainly sounds like it.

According to the book, it's only some diesel models that have this heater for extra comfort. Of course any heat added by the thermostat heater on petrol models helps to warm the system, but the implication is that that's not its primary purpose.

There was, on recent diesel models, a PTC ceramic element housed in the heater box to warm the cabin area quicker.

Nothing to do with the cooling water, block heater or thermostat you understand.