I own a 94 passat GLX, 5 speed manual, 95 k miles, and im having some everapparent issues with my coolant system among other things. I have limited knowledge of cars so the parts i reference may have other names etc , but please bear with me.

My passat's onboard computer lists my approximate running temperature at 240 degrees on a hot day (80-90 degrees ), and anywhere from 215-235 on a cooler day (Below 80 degrees) My thermostat is opening at approximately 205 degrees. Some problems i have had with the system include a ruptured coolant line leading to a destroyed heater core ( replaced at dealership under recall) and a more recently the plastic piece in which my main recirc hose hooks onto the radiator broke off ( only the tip, reattached farther on plastic piece ). right now i am expieriencing a slower coolant leak since the incident.

So i have a few question A) Why such a high running temperature and how do i fix it , and B) What kind of damage would have resulted from high temps from running on little or no cooland for a couple miles ?

Another problem i am expieriencing pertains to my fuel system ( unrelated i believe), When i reach a quarter tank or less, i will lose acceleration or may even stall out while running but only on hot days. I understand im getting lower on fuel, but i am certainly not running it until its bone dry (unless my fuel gauge is off)I use 87 octance gas.

Any help would be appreciated, Thanks!