cooling down while stopped

[kschachn]

The thermostat is not stuck open.

It's a Ford thing. My Ranger does the same, Mom's Maverick does as well. Ford is using that heat to get the transmission temp up quicker, for efficiency purposes. That's why they've moved everything over to liquid-liquid heat exchangers instead of the old air-cooled transmission coolers of the past, they can use the engine heat to increase the system efficiency. Add that to the GDI engines being more efficient (and much smaller) and not generating a lot of heat at idle and you get exactly what you describe. If you have your heater blowing on high, you can watch the temp gauge fall. Once all the metal parts under the hood are up to temp, you've got enough leftover heat that the needle will get to normal and stay there.

If the thermostat is stuck open the ECU will throw a code. It knows the outside temp, and how much fuel it is burning, and can figure out where the temp should be, if it is far enough out of whack, it will set a DTC.

So a poor design then, like the Honda 1.5. Does it also result in fuel dilution?

 

[sammas]

So a poor design then, like the Honda 1.5. Does it also result in fuel dilution?

you know, I think the last time I changed my oil, it did smell a bit more like gas than normal. not enough for me to be concerned though.

 

[ctechbob]

So a poor design then, like the Honda 1.5. Does it also result in fuel dilution?

I'm going to put the fuel dilution of GDI's aside since that's not what we're talking about. None of mine do it, however.

It's not a poor design. (Or at least, it is not an unintended consequence, they've thought of it and it is an engineered outcome.)

It is a smaller, more efficient engine and a system that is using the wasted heat output of the smaller, more efficient engine to raise the efficiency of the entire propulsion system.

FWIW, some of the Escapes and Bronco Sports come with an auxiliary PTC heater to bridge the gap when the car is warming up. So the engineers must have done the calculations and concluded that it is more fuel efficient to bring the drivetrain up to temp faster with engine heat than the electrical energy used to heat the cabin. Which makes sense. You can program the charging system to regenerate that power under braking or other more efficient driving times.

I bash factory engineers all the time, but they're just jumping through the hoops that the EPA requires to sell vehicles these days in the ways they figure best.

 

[kschachn]

Yeah I don’t buy that. Proper thermodynamics of the engine design would ensure operations at the correct set point. These engines seem to have a problem with that concept.

 

[Jetronic]

Yeah I don’t buy that. Proper thermodynamics of the engine design would ensure operations at the correct set point. These engines seem to have a problem with that concept.

Not really, it's all only happening during the warm-up phase. Been like that for ages here in europe, but then a 2.0 was considered a big engine...

 

[mrbreezeet1]

additional details I forgot to post.

the only time ive seen this happen is when the thermostat was stuck open. im thinking this is the case here, but ive never driven a turbo either.

Well if it were me, I would have recommended (if I were the dealer) that you try a new thermostat with no guarantee.......but that would be the first thing that they should do in that case.

 

[mrbreezeet1]

Then a different dealership.

Yes!

 

[mrbreezeet1]

Sometimes but not always. Yeah. The temp drops by half in a matter of a minute or two.

If the thermostat is easy to get to replace it yourself regardless.
Or as stated take it to another dealership if you have one within a reasonable distance.
Or is your warranty only good at that particular dealership?
Or as stated, you could try a hotter thermostat?

 

[mrbreezeet1]

Get yourself a cheap OBD2 scanner that displays realtime data, or better yet a dongle and app. Might cost $20 bucks total. Then watch it on OBD and see how much it drops. A needle moving might only be a few degrees F, which would not be abnormal. These new engines are very thermally efficient, so if its doing it during the warm up phase, it could be a sticky T-stat but doesn't sound like its fully open.

Torque app if you have android, 4-stroke app if you have iphone - either will do it.

Torque App yes.
May as well get Torque Pro, lt's only $5.00.

 

[ctechbob]

Yeah I don’t buy that. Proper thermodynamics of the engine design would ensure operations at the correct set point. These engines seem to have a problem with that concept.

Once the system comes up to temp, it stays there, at the set point. Until it gets there, it uses the heat in the most efficient way they've deemed necessary.

Again, it is not a problem. If it were, the ECU would set a DTC for coolant out of the expected range.

You can take it to the dealer all you want, they're going to return it as normal, because it is.

 

[kschachn]

Oh, I agree the dealer will not repair it. But I still maintain that it is a poor design for an engine. Someone did an inadequate heat flow assessment.

 

[ctechbob]

Oh, I agree the dealer will not repair it. But I still maintain that it is a poor design for an engine. Someone did an inadequate heat flow assessment.

No, they're marching to the beat of the EPA drum, which requires them to get the most MPG out of the thing. It just comes at the expense of 'fast' warmups.

Hence the Aux heater on some of their cars.

 

[mrbreezeet1]

hello guys,

so, ive been having issues and my dealership says they couldn't find anything wrong. so, as my car is warming up, when I stop at a red light, it starts to cool down, like the needle visibly moved back closer to the C. now, it doesnt do this once its fully warmed up, just as its warming up. also, when below freezing, it takes forever to warm up. like 15-20 minutes go drive 45-55mph. dealership said they couldn't find anything wrong with the system.

ford ecosport 1l inine 3.

Did you just get this vehicle, or did you also have it last year, and if so, did it do the same thing last winter?