Fiesta 1.4 tdci overheating problem

[Mario]

Hi!

I have a problem I can`t fix.

So my Fiesta overheats very fast. In 1-2 miles the fan starts to go full on, and the car starts to smoke a lot (silver-gray smoke) and has a rough idle.

I figured its the thermostat, so I changed it. Problem stays.

I figured bad water pump, so I changed it. Problem stays.

Now I have to add, if the car is left to idle eventually after ~10mins car goes back to "normal" no more smoke and the fan goes off. You can than drive it for hours and push it hard with no problem.

It also does not lose cooling water or oil. Oil was also changed recently.


My mechanics next suggestion is oil pump. But I doubt this is it, since the car has no problems once it "settles down" and can be pushed hard too.


+ bonus important funny fact! Car had this problem in autumn and again now. Summer went with no problems!?!


Also: its a mk7 2012 1.4 tdci

Thanx for help Mario

 

[scotman]

Does the heater blower go cold when it indicates that the engine is overheating? I am going to "guess" there is a defective control valve or sensor.
If it is not the cooling system. It is somewhere in the various controls for it. Also, does your car have "active grille shutter" feature? This version has never been available in the states. So i have only limited tdi Volkswagen experience to draw on.

 

[Mario]

No active grill shutter. Heater is blowing extremely hot as soon as it overheats.

I was not aware you don`t have this engine. My guess is that its actually poorly designed thermostat housing and it takes too long for the thermostat to open.

 

[Handy Andy]

Hmmm. To me if the ORIGINAL was installed wrong - you wouldn't have gotten this far with that vehicle because the engine certainly would have failed - miserably.

There are several discussions on other sites about the proper care, feeding and maintenance of a Ford Thermostat - seems to affect their 4 cylinder models more than any other type - and that I cannot explain.

​

The only other condition would be the radiator - and or - a bubble line - used to burp, purge an air pocket within the cooling jacket that can form towards the REAR of the exhaust side of the engine - this is to prevent a condition of lack of coolant to transfer heat away from the upper exhaust valve for number 4 cylinder when the engine is first started or when it's shut off.

Heat can't go anywhere except thru the heads, any oil and the now standing - coolant - so a condition of a soakdown of heat can "bake / coke" the oil and because of tilt of the motor - eventually will be drained back to the oil pan but in the meantime oil can work thru the seals but the heat buildup can form an air pocket - I believe the temperature sensor is located back there too - so if a CRACK in the valve cover has formed or the PCV valve is not working right - plugged or hose is deteriorated and just now sucks air - oil and vapors from it just sit back there at the rear bank of exhaust valves. So it may start draining to the rear past the upper valve cover - causing a smoking condition you don't lose a lot of oil but its' telling me that the seals are weak.. That means it's close to failing when you don't want it to.

So time to roll up the sleeves and look for plugged or kinked bubble-burp purge line and see if the line is plugged or cut - the air pocket that forms can generate the condition for the overheat sensor to think it really blissfully hot back there until the burp can be performed by the engine itself to move / displace the fluid - there is also a circulation issue too -- several hoses are designed to pull some coolant away one for the heater hose, the other to recirculate the coolant past the thermostat back to the water pump and this burp line to force agitation and circulation - if this is bad, that air pocket doesn't get displaced soon enough to balance the sensors readings and it goes into thinking it's overheating.

So if the heater core is working - you have heat - makes this a miserable condition to deal with on a hot day - not so noticeable on the colder days (if any) but if this was going on for a while - I can see where a flush and refill is necessary and a complete overview and check of all the coolant lines to verify nothing is plugging them - is in order.

 

[Mario]

Thank you very much for the reply. What you are describing would fit my problems well and it must be something in this area..

Upon looking at it no cracks are visible nor is the engine "oily" on top, the whole engine is very dry. But I know it would probably be so tiny I wouldn`t see it with the naked eye, at least not while engine is intact. I will do a more thorough inspection of hoses first, as you suggest, if nothing valve cover is also something I can do in my garage. Than its back to the mechanic, and I will advise him to also check first in this direction. Because the oil pump I am pretty sure would not go "OK" all of a sudden, and it`s also not making any sound.

As far as seals go I think they are not weak jet, because smoke comes on when the engine is really hot and you flor it (I have been carefully not to do that a lot). But when the car "settles" there is not even a hint of smoke even pushing it up hill hard. So I think if I solve the problem soon, there wont be a need to replace those as well. Hopefully.

 

[Handy Andy]

Oh ok!

Now I see your reference to the "smoke" is while you drive...ok be careful with this because you don't want to hurt/warp the cylinder head with too much pressure causing this smoke / steam effect thru the tailpipe.

Um, not sure if you can go back in our archives, but there were several threads about those wonderfully made coolant reservoir tanks and their hose and leak issues around them.

Also - Radiator is not out of this either - it too can have problems. A plugged core can make those hoses to the radiator - seem cold - if the fin core is plugged, a restriction forms and the engine can't cool until the core is hot enough to open enough of the pores in the fins to circulate. IF someone put in the WRONG fluid at one time - then refreshed it with the correct fluid, the remaining stuff in the core of the radiator can "form a gel" and requires a lot of heat to release the "gel state" it's in - this condition you'd also have problems with the heater core too - you don't so - unless the core of the radiator is somehow crushed - or plugged -this scenario is less and less likely to be your problem.

It is known that a purge/recirculation line - if plugged, kinked or sent to the wrong port - will cause an overheat because there is not enough flow of the coolant from the engine side of the thermostat to even make the wax-bulb in it heat up enough to begin to open.

​

But when it "warms up" it seems to work just fine? How that can occur is by the radiator fan/shroud forcing air to the engine because it thinks it's hot thru the sensor inside the block - but heat from the engine block overcomes that effect and eventually the thermostat housing allows that valve to open, or that housing that holds the thermostat is somehow warped (the cover that holds the hoses) and requires heat to "reseat" or the thermostat itself can not burp itself so an air pocket forms behind the housing because the fluid cannot circulate properly - there is a bypass hose to recirculate the hot fluid back to the engine as this is it's purpose to force the housing to "feel the heat" so it can open and get to the radiator.

​

Just so you know - several types of gaskets to handle the thermostat and the housing - one can fit the other and if you don't use the right one - the gasket can block the ports the housing uses to circulate the fluid to get the bulb-thingy to even feel heat...

Courtesy of...Engine-Thermostat-h-photo.jpg (575×422) (sprint-motorsports.com)​

IF you look above - there is a brass stem sticking out of the housing that faces or is-set-to - the OUTSIDE (towards the radiator)- this thingy is a "bell-valve" it allows some of the air trapped behind the thermostat to "bleed" out and away from the engine for coolant to displace the air and keep it from overheating the motor in a given hot-spot - which can cause a warped cylinder head if not kept in check. The bleeder Bubble Bell valve is to the UP position when installed to let air escape but little fluid - it too does have a check "vane" on the opposite side of the stem to retain fluid behind the housing so it can circulate coolant and not draw in air.

2011-2019 Ford Fiesta Thermostat - Motorcraft RT-1211
This one is 190 degrees...​

In fact, you really should buy the correct one for your mechanic, then you can have him give you the OLD one from YOUR engine to show they did change this out with your new one - may not save a bunch of money but you have the assurance that you have a thermostat - and it should look something like the two types shown above with A GASKET RING and not a flat felt-based one.

 

[Mario]

I changed the thermostat myself and when I saw the problem was not fixed I also cooked the old (original) thermostat at home and it opened in boiling water. So the fact that previously installed thermostat and the now new one did not make a difference I think it is not that. Same for its gasket or rather the thermostat housing`s gasket. Because this comes like a unit. U cannot buy just the thermostat it comes with the housing an goes on the block of the engine with 4 bolts + a gasket of course.

As for coolant I don`t know about the previous owner, but I am / want to be pretty sure that the coolant wasn`t bad. In fact here we actually have get a lot of opposite problems. Our coolant water can sometimes be very aggressive, to the point that it damages the cooling system from the inside.

 

[Handy Andy]

Interesting, when were from different countries, we have similar vehicles, but different fluids in them...

Well, it sounds like you got your ducks in a row over there, the 1.4L is quite different from the 1.6L we have as "standard" for the USA's version of the Fiesta.

I only hope the hose port routings are correct - if the fluid doesn't circulate - the thermostat will take a really long time before it opens.

You have heat, so there is circulation -

...we feel your pain...

 

[scotman]

Love the images of the components! I am also somewhat concerned about the best way to diagnose this issue with any version of the Fiesta. Obviously, age and system maintenance history is a large factor.
All of the engines in North American fiesta have their own unique issues with their cooling systems. Catastrophic engine failure being the only common outcome.
I think that a proactive maintenance regimen where the owners have shared their experiences, good and bad, will lead to a more realistic and satisfactory ( and less expensive!) Group of Fiesta owners. All cars have their quirks. Most quirks and shortcomings can be dealt with.
Thats some good insights you gave us, Andy!

 

[Mario]

1.4 is different yes. We also have 1.6 but only few opt for it so its rare.

Hoses are mounted correctly, I`ll post a picture of the thermostat housing. When I get to it.

As for the pain, yes its annoying, but well fix it, one way or another


I agree @scotman my car started having problems at the 200k kilometer mark, around 125k miles. Lots of little things. But the engine is another thing.

 

[Handy Andy]

I'm not giving up so quickly - yet...

Even though I may have to run aground with issues around how dealers work - or don't...

I still have a "template" to help ...

BRB...

Sorry if some pics are a little blurry, but this area I'm "shooting" the phone camera with is just by the AC and Alternator side of the motor - under the Intake...

So if you can imagine this...

Now on my car...

The reach to pic this is difficult but here are some other alignment markers to help you...
The PCV valve housing is under the intake too - this shot is by the AC unit and you can see
where the TEMP sensor sits - right by the Thermostat housing on the block.
I also have an Oil Cooler...

So the circulation here is...
FROM HEATER CORE - DOWN TO Oil Cooler
Then UP to 3-way fitting...
(The low pressure "uptake" line")
How do I know this?


So then the Big hose from the Radiator Top is here...

And so is one of the Heater Hoses that GO to the Heater CORE.

This is pretty much the route it takes...
One more tid-bit of advice!
​

 

[Mario]

So if I uploaded the pictures correctly. Here`s my thermostat fixed in the housing. So the hoses could not be switched. Its also on the other side of the engine on my 1.4.

But! I guess I wont need bothering with this no more. My mechanic (actually another one) had a better idea, he says its a plugged exhaust particular filter. With no light to tell the driver it apparently was trying to start the regeneration process. It supposedly let it run hotter for more efficient re-gen. It was I guess too clogged up so it couldn`t clean itself. So they cleaned it and charged 120€. I really hop it does the job. If not, the removal and reprograming of the filter is around 400€.

We`ll see

 

[Handy Andy]

Thank you- sorry to see it was something totally unawares.

We didn't know you had a Diesel - so to be fair - the particulate fitter issue makes sense but not as an overheat condition caused by plugged radiator, this was due to a "emission" control device - in the US we use DEF (Diesel Exhaust Fluid) as a means to "regen and it steam cleans" the particulate filters much like how some smokestacks for Coal and Fuel Oil generators for Electric work - they "rinse out" the soot collected by adding ammonia on the particulate filters with added heat to force the "reburn" of the particulates to reduce the soot produced - reduced down to a carbon ash nitrogen and water - this is just one way - so in your instance we presumed your country had set up a method or means to let you, the owner - know of the process.

IF anyone wanted to know more about DEF used in Diesel engines - look here...
https://en.wikipedia.org/wiki/Diesel_exhaust_fluid

I myself being a former truck Driver - tried to research your 1.4L engine and I kept coming up with Diesel models - but no way to know if this particular engine was Diesel (or low-grade fuel) operation or changed over to Ethanol or Petroleum (Gasoline) .

Wow, glad to know you're alright...this could have gone really bad.

 

[Mario]

Same here for the AdBlue (def) liquid. But my car does not have that.

I really appreciate all the help. If nothing I at least wasn`t changing the oil pump for no reason, like I did the thermostat and the water pump.

Thanks!