Hi , I'm having issues with my 2015 focus zetec s tdci that hopefully someone can help with . The problem is my coolant level dropping below min without obvious leaks . Every time I weekly check it its bellow min . Only for me to top up and it disappear. On realising the cap coolant it bubbles up and overflows out the bottle . You can start the car with cap back on for 20 seconds and the preassure is back. Some further background car is on 96k miles ,no noticable loss in power I think ! Only had it a month nor dose it overheat . No EML light on ,no emulsion on oil filler cap or dip stick. Car had a thermostat replaced a week or so after buying it . The heating did improve ,which was I think a separate issue. Really concerned as I've not long bought the car . Thanks in advance 

2 hours ago, John Burns said:

Hi , I'm having issues with my 2015 focus zetec s tdci that hopefully someone can help with . The problem is my coolant level dropping below min without obvious leaks . Every time I weekly check it its bellow min . Only for me to top up and it disappear. On realising the cap coolant it bubbles up and overflows out the bottle . You can start the car with cap back on for 20 seconds and the preassure is back. Some further background car is on 96k miles ,no noticable loss in power I think ! Only had it a month nor dose it overheat . No EML light on ,no emulsion on oil filler cap or dip stick. Car had a thermostat replaced a week or so after buying it . The heating did improve ,which was I think a separate issue. Really concerned as I've not long bought the car . Thanks in advance 

Could be a heater matrix issue, have a feel at your drivers side mat to see if it's wet. If so, you could be lucky and it may be the 'O' ring gone from the pipe into the matrix. If it's the matrix itself, well, let's just discuss the 'O' ring for now...

Thank you ,will check ,now that you mention it I have heard gurgling coming from behind the dash .

Hi John, did you resolve this issue? was it the Heater Matrix? Was wondering how this would cause the system to pressurise and remain pressurised.

 

Hi ,yes mate . Unfortunately the head gasket has gone . Finance co independent inspector confirmed it last week . Also just received his report. Thankfully he found in my favour . 1500miles is al ive done since 6th nov . Will definitely know now to check that in the future ,although im unlikely to get snother diesel tbh. I had done basic check for head gasket but never thought it would be a issue on a 6 year old car. Admittedly it had seen serious use in those years as a fleet car ive now discovered. Currently running around in a old mk1 focus estate till its all sorted out .

Cheers for letting me know. Have a similar issue that the system pressurises and retains the pressure even when cold but i don't appear to be loosing any coolant.

The level returns to normal when the pressure is released.

Had the car for 4 years so got fingers crossed that its not the head gasket and may be either the oil cooler or the EGR cooler... 

Im by no means diagnosing your issue mate but sounds ominously familiar. The engineers report says presence of exhaust gasse and loss of preassure.  Most probably head gasket. Im not sure if it could also be egr it didn't mention it though . I was also getting more than normal steam from exhaust on cold mornings with a sweet smell to it . Car also took ages to warm up . I also tried a new expansion tank cap bled heater matrix and new thermostat to.no if avail . Not sure if any of this is any help to you . Im waiting for the dealers response now. 

Thanks John, looking quite familiar. Car and Heater taking an age to warm up. Had the Thermostat changed already. Not noticed the smell or steam from the exhaust. Temperature guage gets to the midway point on the guage but will at intervals will drop to midway between the mid point and the bottom of the guage. Then return back to the midpoint. When you depressurise the colant tank the fluid level returns to the correct position. Good Luck.