Help needed please!

I have a 2014 1.6 diesel focus titanium  navigator estate. Its the model with sync, satnav, and climate control, and is a great workhorse.

 

Recently I have experienced a odd probelm where for the first 5-10 miles of any journey the temperature gauge and climate control behave oddly:
Firstly the temp gauge climbs to the normal position as usual. The climate control on "Auto" seems to work, albeit weakly.
Then, the temp gauge drops rapidly back to stop - in 4 or 5 seconds. The heater then seems to work a bit better.
The temp gauge will then slowly climb back to the normal position, and the heater seems to work less well.

This  cycle of the temp gauge dropping rapidly to zero, heater working better, gauge climbing slowly back to normal, heater working less well is then repeated a further 2 or 3 times.

After @ 5-7 miles it seems to stabilise with gauge reading normal and the heater working properly.

 

My local garage diagnosed a sticky thermostat and changed that, however the problem remained. They then checked the temp gauge with their diagnostics and say its working fine. They did say that  live data from the ECU shows a 30 degree drop in water  temp when the gauge falls back to zero.
They say  the thermostats is a wax one and acts quite slowly, so its unlikely that it would open or shut quickly enough to cause the rapid gauge fluctuation.

 

The garage and me are stumped..... They say it wont do any harm, but that they they dont know whats wrong. Nevertheless its irritating and it should be like that.

Has anyone else experienced this kind of thing? Is there any other automatic valve or thermostat in the cooling system, other than the main one, that could be faulty?
 

 

Many thanks in advance!

 

 

Our 2014 Cmax 1.6 tdci does exactly the same thing.  Diesels are very thermally efficient its takes an age for them to heat up ours takes a good 15-20 mins to warm up fully.  Also when sitting in traffic the temp gauge does drop from the normal position with heaters on full especially in colder weather.   I have known ours drop to the cold position after being driven for an hour.

What's your coolant level like, does it drop at all?  You may have an air lock going round the system since the stat change.

Air in the heaters will cause them to worsen, air by the temp sensor will cause a false reading.

has the temperature sensor been checked to see if ok and connector is on fine.  I have no idea how high or low the temperature sensor is situated, but I agree with the comments about coolant level, if the coolant level goes below the level of where the sensor is situated it is likely to give an incorrect reading (giving a reading lower than it should) 

So a diesel takes ages to heat up, some times they are supplemented with electric Aux heaters to help this, anyhow. It will heat up to around 85c then the thermostat will open, this normally results in a drop in temp as the coolant is now flowing through the radiator. depending on how cold it is will depend how quick it drops., mind that temp gauge isn't 0-120 or whatever it is on yours, it will be something like 60-120. Dropping 20c isn't outside the realms of possibility.

once the thermostat is open that coolant will be cooler which in turn will make your inside air cooler then with it closed.

So the it sounds like its doing what it should be albeit fairly extreme which is likely due to the cold weather., the real question should be, why is it not as warm as you would expect.

I would check what temp the thermostat opens up at first, you can use forscan to get a more accurate reading. it should be around 80-85c. watch it climb then it will suddenly drop.

in any case, even if it is 60c you should be plenty warm enough so again the real question should be, why is that heat not getting in to the cabin.

Check for airlocks first. then consider flushing the coolant out and replacing it, consider having the heater matrix flushed out as well it cant transfer heat if its not working. fans, cablin filters, try different blower positions

the gauge reads midway at 45c coolant temp on my 1.0 ecoboom  and stays there regardless of temp rise up to 90c running temp. to get to running temp last week took approx  11 miles

Is your shutter grill jammed open or shut?, maybe its open and over cooling

But sounds like an air lock to me

Hi did you ever find a fix for this? Mine is doing just the same, iv had the thermostat replaced and oil cooler replaced but still no joy, temprature is still up and down.

Hi

apologies for bringing up such an old post

i have a 2012 focus zetec s tdci and it does the exact same thing

temp guage up and down causing a change in heat temprature just as explained above. 

Have had cambelt and water pump replaced.  Thermostat replaced. Expansion cap replaced. 

Did you find a fix to this irritating problem

 

any advice would be appreciated

thanks in advance

On 2/27/2020 at 10:32 PM, Slik945 said:

Hi

apologies for bringing up such an old post

i have a 2012 focus zetec s tdci and it does the exact same thing

temp guage up and down causing a change in heat temprature just as explained above. 

Have had cambelt and water pump replaced.  Thermostat replaced. Expansion cap replaced. 

Did you find a fix to this irritating problem

 

any advice would be appreciated

thanks in advance

Can I ask did you ever fix this problem? I have a grand c max, with exactly the same problems, I have changed all the same components and still have the same problem. The garage is stumped..

Hi I had this problem alongside a issue over 3000 revs sometimes oing into limp mode. Changed fuel filter fixed both issues 2014 1.6 diesel 

 

Coincidence or not for 25 quid worth a go 

Hi All,

Don’t suppose any solution was found to this.

Very similar to post for Ford Focus 1.6 TDCI Diesel. 
 

Would add another problem I have experience is when running on motorway for a while temp gauge will rise about the normal (but not fully up) and go into limp mode before dropping back down. 
 

Any solutions or outcomes of others would be greatly appreciated. 

Hello everyone, I have a Focus 1.6 from 2014 with the same fault. Has anyone found a solution to the problem? Thank you all.

@Paulo you don't say if its a tractor or not ?

the OP at the top seem to be describing a rather lively opening of the cooling thermostat - most cars do it but they aren't meant to be so noticeable,

start off on the short rapid warm up cooling circuit (everything is good), then the stat opens late and way too fast (possibly coz its been overheating a bit) and suddenly a massive influx of cold rad water over cools things and it muddles about .... maybe they eventually built a thermostat that opens when it should progressively (assuming its a mechanical one), if its some electronic stupidity, maybe needs a software update

 

But the real reason I'm bothering to post is re a chat I had with a mate yesterday about morons that do an EGR delete - two MAIN reasons they recycle tractor exhaust gas is to keep the engine warm enough that 1) the oil does its job and 2) the interior heater gets to function !!!!

petrol cars must ALWAYS have the perfect air fuel ratio (or they just go bang and you walk to work) - but tractors work differently - and ingest loads of air, only using only as much as there is tractor death fuel to burn...  so when you drive in low ambient temps the engine gets colder and colder and the heater gives up, unless you recycle loads of exhaust gases via the EGR (exhaust gas recirculation)

way back when - my dead standard fully functional 6 pot BMW 2.5 ltr turbo tractor would end up on motorways with NO heating when it was -5C outside (and that was even when the EGR spat most of the exhaust gases back in trying to keep things hot)

 

the Japanese, who care about engineering - had to reinvent far more efficient heater matrix's for their cars to compensate for cold coolant temps

the Japanese always knew (just like your governments ALL did) that tractor fuelled vehicles are death machines (so don't allow them to be sold in their country), - they only started making tractors (or they'd go bust) for the EU death zone - where the governments lied, cheated and reduced the price of death fuel so they can kill your children 

 

1 hour ago, Botus said:

@Paulo you don't say if its a tractor or not ?

the OP at the top seem to be describing a rather lively opening of the cooling thermostat - most cars do it but they aren't meant to be so noticeable,

start off on the short rapid warm up cooling circuit (everything is good), then the stat opens late and way too fast (possibly coz its been overheating a bit) and suddenly a massive influx of cold rad water over cools things and it muddles about .... maybe they eventually built a thermostat that opens when it should progressively (assuming its a mechanical one), if its some electronic stupidity, maybe needs a software update

 

But the real reason I'm bothering to post is re a chat I had with a mate yesterday about morons that do an EGR delete - two MAIN reasons they recycle tractor exhaust gas is to keep the engine warm enough that 1) the oil does its job and 2) the interior heater gets to function !!!!

petrol cars must ALWAYS have the perfect air fuel ratio (or they just go bang and you walk to work) - but tractors work differently - and ingest loads of air, only using only as much as there is tractor death fuel to burn...  so when you drive in low ambient temps the engine gets colder and colder and the heater gives up, unless you recycle loads of exhaust gases via the EGR (exhaust gas recirculation)

way back when - my dead standard fully functional 6 pot BMW 2.5 ltr turbo tractor would end up on motorways with NO heating when it was -5C outside (and that was even when the EGR spat most of the exhaust gases back in trying to keep things hot)

 

the japanese, who care about engineering  - always knew (just like your governments ALL did) that tractor fuelled vehicles are death machines (so don't allow them to be sold in their country), - only started making them or they'd go bust - for the EU death zone, where the governments lied, cheated and reduced the price of death fuel so they can kill your children - had to reinvent far more efficient heater matrix's for their cars to compensate for cold coolant temps

 

My car's fuel is diesel and I haven't made any changes to the engine, the EGR continues to do its job.

Hello to all,

                 Came across this discussion while searching for an answer to pretty  much an identical problem with my 2014 Focus 1600 Tdci. Additionally however I have recently noticed that when I switch on the air conditioning the gauge slowly falls and when I switch it back off again the gauge slowly  returns to normal. Initially on starting from cold I have noticed some while ago that the gauge climbs to approx 75 degrees and then drops back to around 65 but then gradually went up to normal at approx 88-90. A couple of years back while towing a caravan the gauge dropped down to approx 65 while I was going down a long hill, low gear, no accelerator, engine braking etc even though I had probably been towing for about a hundred miles at the time. I thought that the thermostat should start to close up if the air flow through the radiator was causing the water to cool in order to keep the temperature up. The thing is that the car give every impression while driving that there is nothing wrong at all apart from the gauge going up and down. Does'nt make any sense. Any ideas out there would be welcome. Thanks in advance.

14 hours ago, Rob of Stafford said:

Hello to all,

                 Came across this discussion... I recently noticed that when I switch on the air conditioning the gauge slowly falls...

 

when the AC is operational it usually brings in a cooling fan to ensure it retains adequate air flow over the condenser at slow vehicle speeds / heavy workload
as this AC condenser is at the front of the car - sitting in-front of the engine radiator - it often introduces additional engine cooling too

as the world of engineering talent left the building years ago, idiots with junk software fiddle with stuff they have no idea about, and the accountants ensure everything in the corporation is a complete disaster - expecting anything to operate correctly is futile.... 

you could TRY a stat but don't expect to get far... 
if the map has been got at by kids are us - the EGR is likely doing anything but something helpful
if the EGR has never been cleaned its likely only partially operational and about to burn out

DIESELS are death machines they always knew it - should never have been allowed for motor cars, but it works the way they want it, alongside the poison in your food, and the fluoride in your drinking water

Thanks Botus that has cheered me up no end. Its just that I had not seen this happen with the air con before so I assumed there to be a problem.