1994 Nissan Sentra Coolant Loss

Hi there,

Thank you for the donation,

When you shut down the engine it becomes a big heat sink, that is it is still heating up as the circulation of coolant has stopped and in most cases the cooling fans aren't cutting in, (VW's for instance will turn on the fans if the car ids off and coolant temp goes above trigger point) my feeling is that the engine may be running a little warmer than normal and as the engine is shut down the heat sink effect is causing this increased temp and localized boiling, I would replace the thermostat, flush the coolant have the radiator professionally cleaned & flow tested and ensure that the fans are switching on at the correct temp,

start here.

Mark (mhpautos)