I posted on here about intermittent cabin heat and was informed it was due to coolant loss.


A bit of an update on this which may help other members.


It was indeed loss of coolant but it was not leaking all the time, some days I would have to top up the header tank a couple of times a day other times once a week. The car has been in the garage on many occasions but could not detect any leaks.
Last week I took it in again due to more coolant loss and they had the engine running for a few hours, they were about to give up and they spotted a small trickle down the side of the rad.


After investigations it was coming from the plastic egg cup sized component (it has the metal pressure cap on it, and bolted to the slam panel near to the drivers side headlamp, RHD model) it also has the pipe running from the header tank to it, it has a small hair line crack in it and only really leaks when the thermostat opens to allow the rad to cool the fluid, since its been very cold this has not been happening hence the leak is not always present.
Dealer only part at a cost of £98 so I used milliput to seal the crack. I have not been on a good run yet but it looks promising.


car is a 1.8 TS2 2007 model with 77K on the clock