I have coolant leaking from the Reservoir or somewhere in that area. What is strange is after sitting a week, the system is still pressureized which tells me the cap and reservoir are fine. From the reservoir a line runs to a metal cylinder. This has stains around the top, but not enough to account for the amount of fluid under the car, wrong location as well. Can someone tell me the function of this cylinder. I can see how it could be the expansion tank, but what I dont see is how this cylinder is vented. I was going to remove this wknd and figure the system out, but was hoping someone could give a pointer. Car runs fine, never runs hot, no
oil in the coolant and no coolant in the
oil so not concern about a blown gasket.. i hope.