using dexcool now heater coor is leaking, coincidence?

[stang5]

I have 97 eclipse (non turbo)owned since new, I've replaced the coolant twice with prestone dexcool(orange stuff). For the past month I can smell a strong coolant odor coming from the air vent when the heater is turned on. I'm guessing its the heater core leaking, could the orange prestone coolant caused it or just coincidence? the car only has 45K miles, I plan on using some prestone coolant stop leak. I need some input, thanks

 

[Ray H]

If air wasn't purged properly from the entire cooling system (including the heater core) during one or both previous changes, or was allowed in due to a slow leak, faulty radiator cap, or improperly filled overflow bottle, what type of antifreeze was installed may be irrelevant - an airlock's a ticking time bomb for eventual corrosion perforation, regardless.

 

[Meistersinger]

I'm just curious, but why would you have replaced Dexcool twice on a vehicle with only 45k miles on it? With Dexcool being an extended life coolant, the possibility of introducing air into the system is just too high to change this early and often.

 

[stang5]

I first replace the factory green coolant after 2 years with the 5 yr/150k miles prestone orange coolant and 5 years later I change it again, I figured the prestone 5/150 will last 5 years or 150K miles wichever comes first.