ever month or so i have a slight overheating problem........

not loosing any coolant it just ends up in the expansion tank (tank almost full) and the coolant is low in the header tank

car runs fine until this happens then only a rise in temp, no engine loss of power or anything like that.

fan comes on ok

heater warms up as normal and engine operating temp is reached in the usual time

the only thing is that there is an oily residue on the sides of the expansion tank when i remove the excess coolant, i say oil, its not oil as you would expect is a sort of sticky if you know what i mean??

any ideas?

the car is a MY06 spec d sti

thanks steve

 

that needs looking at,before it gets ££££££££££££££££

 

i will call in the warranty

i also have the dreaded rear shock knock and while there at it the driver window rattles a bit when open

 

My spec D has always done this - but the problem comes and goes and can be fine for several months at a time.
It is something to do with losing the vacuum caused when the main coolant system cools down. This is meant to suck back the expansion tank contents, but it seems that there is an air leak.
Mine is going thorugh a bad patch at the moment and I'm having to reck myslef.
The build up seems to be brown/black solids rather than oil.
I had mine tested for HG leaks but this didn't show any problems.

Nick